Best Caramelized Onion Tart Recipes

CARAMELIZED ONION, MUSHROOM AND GOAT CHEESE TART

Steps:

• Preheat oven to 400 degrees F.
• Using a mandolin or super-sharp knife, cut onion into paper thin slices. Clean and slice the mushrooms.
• Heat 1 tablespoon oil in a skillet over medium heat; add onion and saute until caramelized. Transfer to a bowl and set aside. Heat remaining teaspoon of oil in skillet over medium-high heat. Add mushrooms and saute until they release all their liquid and most of it boils away, should take about 5 minutes. Combine caramelized onions with mushrooms and saute together briefly; season with salt and pepper. Remove the pan from heat.
• Unfold puff pastry onto a floured surface; cut in half lengthwise to form 2 long rectangles. Gently roll out each rectangle to approximately 5 by 14 inches and place on cookie sheet. Trim edges by 1/4-inch strips all around; set strips aside. Break 1 egg into a small bowl; beat slightly. Brush edges of pastry with some of the egg. Use trimmed strips to make a raised border on each. Brush entire surface with remaining beaten egg. Prick the interior of pastry all over with a fork. Bake until pale gold, about 10 minutes. If pastry has puffed up inside edge, press it down gently. Set aside.
• Meanwhile, combine remaining eggs with 6 ounces goat cheese and blend until smooth. Spread the mixture onto pastry. Return to oven and bake just until set, about 4 minutes. Add the thyme to the mushroom mixture. Remove cookie sheet from oven and spread with thyme-mushroom mixture. Crumble remaining cheese on top. Just before serving, broil tarts on low heat for 2 to 3 minutes, until tarts are warm and cheese softens.

CARAMELIZED ONION POTATO TART

Steps:

• Preheat oven to 350 degrees F.
• Set a large skillet over medium heat and add 4 tablespoons of olive oil. Add sliced onions and cook over medium heat for 10 to 12 minutes until they are tender and brown all over.
• Using a mandolin (or sharp knife), finely slice the potatoes into rounds (you can place them in a bowl with a wet towel over the top to stop them from going brown while you work). Place the potatoes into a bowl and season with salt and pepper. When ready, add the onions and toss to combine without breaking potatoes.
• Add about 1 tablespoon water to the same pan the onions were cooked in and allow it to come to a bubble. Using layered paper towels, wipe the pan clean.
• Add some extra-virgin olive oil to the pan and add the potatoes to the pan, making sure the potatoes are flat. Top with the diced butter.
• Take a piece of parchment paper and fold in half. Find the middle of the parchment along the crease and hold in place with your finger. Taking the right side of the parchment, pull it towards the center and fold it straight down to create a diagonal edge. Fold the parchment in half to create a triangle. Place the pointed edge in the middle of the saute pan on top of the potatoes to find its radius. Make a marker of where the pan edge ends (or starts). At this point you can cut the parchment at this marker and open to reveal a circle.
• Cover the potatoes with the parchment paper and press down. Drizzle some extra-virgin olive oil over the top so it down burn and rub it in.
• Place the pan into the oven on the top rack and bake for about 45 minutes.
• When done remove from oven and run a knife around the edge to separate from the pan. Place a large plate on top of the saute pan and flip. Remove the saute pan. Allow to cool slightly before cutting into slices.

CARAMELIZED ONION TART

Steps:

• Thaw the pastry sheet at room temperature for 40 minutes or until it's easy to handle. Heat the oven to 400 degrees F. Line a baking sheet with parchment paper or spray with vegetable cooking spray.
• Heat the oil in a 12-inch skillet over medium heat. Add the onion and cook for about 15 minutes or until golden, stirring often. Season to taste and let cool.
• Unfold the pastry sheet on a lightly floured surface. Roll into a 12-inch square. Place on the prepared baking sheet. Brush the edges of the square with water. Fold over the edges 1/2 inch on all sides, pressing firmly with a fork to form a rim. Prick the pastry thoroughly with a fork.
• Spread the onion mixture over the pastry crust. Top with the gruyere and parmesan cheeses and sprinkle with the chives.
• Bake for 20 minutes or until golden and bubbly. Cool for 5 minutes on a wire rack. Cut into approximately 3 x 2-inch rectangles. Serve warm.

ROASTED BUTTERNUT SQUASH AND CARAMELIZED ONION TART

Steps:

• On a lightly floured surface roll out dough into a 12-inch round (about 1/8 inch thick). Fit dough into an 11-inch tart pan with a removable fluted rim. Freeze shell 15 minutes.
• Preheat oven to 375°F.
• Line shell with foil and fill with pie weights or raw rice. Bake shell in middle of oven until edge is pale golden, about 20 minutes. Carefully remove foil and weights or rice and bake shell 10 minutes more, or until bottom is golden. Leave oven on. Cool shell in pan on a rack.
• Halve squash and scoop out seeds. Lightly brush each cut side with about 1 teaspoon oil and on a baking sheet roast squash, cut sides down, in middle of oven 40 minutes, or until soft.
• While squash is roasting, thinly slice onion and in a heavy skillet cook in 1/2 tablespoon butter and remaining 1 1/2 teaspoons oil over moderate heat, stirring occasionally, until soft and golden brown, about 20 minutes.
• Cool squash and scoop out flesh. In a food processor purée squash. Add whole egg, egg yolk, and cream and blend well. Transfer mixture to a large bowl and stir in cheeses, herbs, onion, salt, and pepper to taste. Pour filling into shell, smoothing top.
• In a small skillet melt remaining tablespoon butter and stir in bread crumbs until combined well. Sprinkle bread crumb mixture evenly over filling. Bake tart in middle of oven 40 minutes, or until filling is set. Cool tart in pan on rack 10 minutes and carefully remove rim.

GOAT CHEESE, TOMATO, AND CARAMELIZED ONION TART

Steps:

• Preheat oven to 425 degrees. Brush an 18-by-12 1/2-inch rimmed baking sheet with oil. Place dough on sheet; press into a rounded rectangle, about 14 by 12 inches.
• Heat 2 tablespoons oil in a mediumskillet over medium-high heat. Add onions and salt. Cook, stirring occasionally,until golden, about 12 minutes; transferto a bowl. Add tomatoes and remaining2tablespoons oil to the skillet. Cover;cook, stirring occasionally, until tomatoes collapse, about 10 minutes.
• Scatter olives, onions, tomatoes, andcheese over dough. Bake until crust isgolden, 25 to 30 minutes. Let cool 10 minutes. Serve, garnished with rosemary.

CAULIFLOWER AND CARAMELIZED ONION TART

Steps:

• Position rack in center of oven; preheat to 425°F. Toss cauliflower with 1 tablespoon olive oil in large bowl. Spread on large rimmed baking sheet, spacing apart. Sprinkle with salt and pepper. Roast 15 minutes; turn florets over. Continue roasting until tender, about 25 minutes longer. Cool cauliflower, then thinly slice. Drizzle with truffle oil; toss. Reduce oven temperature to 350°F.
• Press pie crust onto bottom and up sides of 9-inch-diameter tart pan with removable bottom. Line pie crust with foil; fill with pie weights. Bake crust 20 minutes. Remove foil and pie weights; bake until crust is golden, about 5 minutes, pressing crust with back of fork if bubbles form. Cool crust. Maintain oven temperature.
• Heat remaining 1 1/2 tablespoons olive oil in heavy large skillet over medium heat. Add onion; sprinkle with salt and pepper. Cook until onion is deep golden brown, stirring occasionally, about 40 minutes. Cool slightly. DO AHEAD Can be made 1 day ahead. Store crust at room temperature. Cover and chill cauliflower and onion separately.
• Brush bottom and sides of crust with mustard. Spread onion in crust. Arrange cauliflower evenly over. Set tart on rimmed baking sheet. Whisk eggs and next 4 ingredients in medium bowl. Stir in Gruyère. Pour mixture over filling in tart pan; sprinkle with Parmesan. Bake until tart is golden and center is set, about 40 minutes. Transfer to rack; cool 15 minutes before serving.

CARAMELIZED ONION TART WITH OLIVES

Steps:

• Preheat oven to 425 degrees. Melt butter with oil in a skillet over medium-high heat. Add onions and thyme, and cook until onions are golden and soft, about 10 minutes.
• On a lightly floured surface, roll out pastry, and trim to an 8 1/2-by-15-inch rectangle. Place on a parchment-lined baking sheet, transfer to oven, and immediately reduce oven to 400. Bake until pastry begins to rise, about 12 minutes.
• Arrange onions in a single layer over pastry, leaving a 1-inch border around edge. Top with olives and anchovies if using. Bake for 15 minutes. Reduce oven to 375 degrees, and bake until puffed and golden brown, about 15 minutes more (tent with foil if crust browns too quickly). Cut into squares.

POTATO AND CARAMELIZED ONION TART

Steps:

• Preheat the oven to 375 degrees F.
• Prepare the pie crust according to package instructions. Flatten into a disk and chill in the refrigerator while preparing the filling.
• In a large saute pan over medium heat, heat the canola oil. Add the onions and season with salt and pepper. Cook, stirring occasionally, until the onions are dark golden brown, 10 to 15 minutes. Remove from the heat.
• In the meantime, using the slicing blade attachment of a food processor, or with a box grater, slice half the potato into 1/8-inch-thick slices. Place in cold water to avoid browning. (Reserve the remaining half of potato for another use, such as Round 2 Recipe Open Faced Roast Pork and Onion Sandwich.)
• In a small bowl, stir together the cream cheese, Italian seasoning, mustard and season with salt and pepper.
• Remove the pie crust from the fridge and roll into a 12-inch round about 1/4-inch thick. Place on a parchment-lined baking sheet. Spread the cream cheese mixture in an even layer over the pie crust, making sure to leave a 1-inch border around the edge.
• Dry the potatoes thoroughly and place an even layer on top of the cream cheese, overlapping slightly to fit and keeping 1/2-inch from the edge of the cream cheese. Over the top of the potatoes place an even layer of caramelized onions. (Reserve 1/2 cup of the onions for another use, such as Round 2 Recipe Open Faced Roast Pork and Onion Sandwich.) Fold over the edges of the crust to create a 1-inch-wide border around the tart filling.
• Bake until the crust is golden and the potatoes are cooked through, 30 to 35 minutes. Allow to cool for 5 minutes before slicing.

CARAMELIZED ONION AND ROASTED RED PEPPER TART

Steps:

• Dough:.
• Dissolve yeast and honey in warm water in a large bowl; let stand for 5 minutes.
• Lightly spoon flours into dry measuring cups, and level with a knife. Stir 1 cup bread flour and 1 tablespoon oil into yeast mixture. Cover and let rise in a warm place (85°F), free from drafts, 1 1/2 hours or until bubbly.
• Stir in 1/2 cup bread flour, whole wheat flour, and 1 teaspoon salt.
• Turn dough out onto a floured surface. Knead until smooth and elastic (about 10 minutes); dough will feel tacky. Place dough in a large bowl coated with cooking spray, turning to coat top. Cover and let rise in a warm place (85°), free from drafts, for 1 hour or until doubled in size. (Press two fingers into the dough. If indentation remains, the dough has risen enough.) Punch dough down; cover and let rest 10 minutes.
• Topping:.
• Heat 1 tablespoon oil in a 12-inch nonstick skillet coated with cooking spray over medium-high heat. Add onion, and cook for 5 minutes, stirring frequently. Stir in 1 teaspoon salt, thyme sprigs, garlic, and bay leaves; cook for 15 minutes or until deep golden brown, stirring frequently.
• Remove from heat. Discard thyme sprigs and bay leaves.
• Preheat broiler.
• While onion is cooking, cut bell peppers in half lengthwise, discarding seeds and membranes. Place the pepper halves, skin sides up, on a foil-lined baking sheet; flatten with hand. Broil for 15 minutes or until blackened. Place in a zip-top plastic bag, and seal. Let stand for 15 minutes. Peel and coarsely chop.
• Preheat oven to 425°F.
• Roll the dough into a 12 x 8-inch rectangle. Place the dough on a baking sheet coated with cooking spray. Top with the onion mixture and the chopped bell pepper. Sprinkle with black pepper. Bake at 425°F for 25 minutes or until the crust is golden brown. Cool slightly. Sprinkle with chopped thyme. Cut into 8 squares, and cut each square in half diagonally. Garnish with thyme sprigs, if desired.

ROASTED BUTTERNUT SQUASH AND CARAMELIZED ONION TART

Steps:

• Using a prepared pie crust or your favorite crust recipe. On a lightly floured surface roll out dough into a 12-inch round (about 1/8 inch thick).
• Fit dough into an 11-inch tart pan with a removable fluted rim.
• Freeze shell 15 minutes.
• Preheat oven to 375°F.
• Line shell with foil and fill with pie weights or raw rice.
• Bake shell in middle of oven until edge is pale golden, about 20 minutes.
• Carefully remove foil and weights or rice and bake shell 10 minutes more, or until bottom is golden.
• Leave oven on.
• Cool shell in pan on a rack.
• Halve squash and scoop out seeds.
• Lightly brush each cut side with about 1 teaspoon oil and on a baking sheet roast squash, cut sides down, in middle of oven 40 minutes, or until soft.
• While squash is roasting, thinly slice onion and in a heavy skillet cook in 1/2 tablespoon butter and remaining 1 1/2 teaspoons oil over moderate heat, stirring occasionally, until soft and golden brown, about 20 minutes.
• Cool squash and scoop out flesh.
• In a food processor purée squash.
• Add whole egg, egg yolk, and cream and blend well.
• Transfer mixture to a large bowl and stir in cheeses, herbs, onion, salt, and pepper to taste.
• Pour filling into shell, smoothing top.
• In a small skillet melt remaining tablespoon butter and stir in bread crumbs until combined well.
• Sprinkle bread crumb mixture evenly over filling.
• Bake tart in middle of oven 40 minutes, or until filling is set.
• Cool tart in pan on rack 10 minutes and carefully remove rim.

CABBAGE AND CARAMELIZED ONION TART

Steps:

• Heat 1 tablespoon of the olive oil in a large, heavy nonstick skillet over medium heat. Add the onions, and cook, stirring, until they begin to sizzle and soften, about three minutes. Add a generous pinch of salt and the garlic. Stir everything together, turn the heat to low, cover and cook slowly for 45 minutes, stirring often, until the onions are very soft, sweet and light brown.Meanwhile, heat the remaining olive oil over medium heat in another large skillet. Add the cabbage. Cook, stirring often, until it begins to wilt, then add salt and pepper to taste. Continue to cook for another 10 to 15 minutes, stirring often, until the cabbage is tender and fragrant. Stir in the onions, simmer together uncovered for about five minutes or until there is no longer any liquid in the pan, and remove from the heat.
• Heat the oven to 350 degrees. Oil a 9- or 10-inch tart pan and line with the dough. Beat the eggs and milk in a bowl and season with salt (about 1/2 teaspoon) and pepper. Stir in the onions, cabbage and cheese, and combine well. Scrape into the tart pan, and place in the oven. Bake 40 to 45 minutes until the top is lightly browned.

CARAMELIZED ONION AND SWEET POTATO TART

Steps:

• Make Pastry: combine flour, butter, shortening and salt and lightly mix until it resembles breadcrumbs. Blend in enough water to form a dough. Wrap in clingfilm and refrigerate for at least 30 minutes.
• To make Tart: Pare yukon gold potatoes, slice 1/4 inch thick and put in cold water.
• Pare and slice sweet potatoes and stand in cold water. do the same with the parsnips.
• Steam potatoes, parsnips and sweet potatoes until al dente. Set aside.
• Heat oil and saute onions until caramelized and golden brown in color. Add Herbes de Provence and garlic and saute for 3 more minutes. Set aside.
• Mix manchego, gruyere and cream together in bowl and set aside.
• Preheat oven to 350°F.
• Roll out pastry and press into bottom and sides of a 9 inch springform pan.
• Layer potatoes, sweet potatoes and parsnips in tart and sprinkle onions and cream/cheese. Repeat until all ingredients are used.
• For maximum appearance make sure to finish the top layer with sweet potatoes, then caramelized onion.
• Bake 45 minutes in preheated oven.
• Remove from oven and allow to sit for 20 minutes.

RATATOUILLE TART WITH CARAMELIZED ONION-TOMATO JAM

Steps:

• In a high-sided saute pan with a lid, heat the olive oil over medium heat. Add the onions, season with the salt, cover and cook until they are wilted and soft, about 10 minutes. Remove the lid and cook the onions until they are golden and caramelized, stirring often, about 20 minutes more.
• Stir in the garlic and saute 1 to 2 minutes. Add the tomatoes and cook an additional 10 minutes. Add the remaining ingredients, bring the mixture to a boil and then reduce the heat to a simmer. Stirring consistently, cook until the tomatoes breakdown and the jam becomes thick, about 20 minutes.
• Yield: 3 cups
• Preheat the oven to 400 degrees F.
• Roll the puff pastry out on a floured surface to a rectangular shape, about 12 by 10 1/2 inches. Transfer the pastry sheet to a parchment-lined baking sheet. With the tines of a fork, dock a 1/2-inch border around the edge of the sheet and dock the center of the sheet a few times as well. This will prevent the dough from rising as it cooks.
• Spread the Caramelized Onion-Tomato Jam evenly over the pastry, leaving a small border around the edge of the pastry. Layer the tomatoes, eggplant, yellow squash and zucchini in overlapping rows, or in whatever pattern you like. Sprinkle the roasted red peppers around the tart. Drizzle the assembled tart with a little olive oil, making sure to brush a little on the edges, season with salt and pepper and top with half of the fresh oregano.
• Bake until the pastry is golden brown and puffed, 20 to 25 minutes. Remove from the oven and immediately sprinkle with the goat cheese and the remaining 1 1/2 teaspoons oregano before serving.

FIG , CARAMELIZED ONION AND BLUE CHEESE TART

Steps:

• Preheat oven to 400°F.
• Soak figs in hot/boiling water for 1/2 hr.to soften. Set aside.
• Lightly coat baking tray with olive oil.
• Spread pastry on baking tray, join edges and pierce with fork to allow air to escape during baking.
• Bake until light brown (approx. 5-7 min.).
• Cook onions in butter and olive oil over medium heat until soft caramelized.
• Add brown sugar, salt and pepper, thyme and cook over low heat for 5 minute.
• Add drizzle of balsamic vinegar in last 2 minutes.
• Pour onion mixture over pastry covering to edges.
• Add figs (cut into small chunks).
• Sprinkle with cheese.
• Drizzle with olive oil.
• Bake at 400F fro 10-12 minutes.
• Cool before cutting.
• Cut into appetizer size pieces.

MUSHROOM AND CARAMELIZED ONION TART

Steps:

• Preheat oven to 400 degrees F.
• Place the flour, butter and salt in the bowl of a food processor. Pulse a few times to break up butter into little pieces... mixture should resemble coarse corn meal. With the machine running, add the water a tablespoon at a time until the dough holds together when squeezed. Gather the dough together and form into a rectangle. Wrap in plastic wrap and refrigerate for one half an hour.
• In the mean time, heat the butter and olive oil in a large sauté pan. Add the mushrooms, stir to coat, spread out in the pan and allow to cook, undisturbed for a couple of minutes. Stir once and redistribute, continue cooking in this same manor until mushrooms are golden brown. Remove from pan and set aside.
• Add onions to the same sauté pan; add additional olive oil is necessary. Sauté until caramelized well, season with thyme, salt and pepper.
• Divide pastry in half. Roll each piece of pastry into long strips, about 4 inches by 8 inches. Place on a parchment lined baking sheet and crimp the edge of the dough to create a rim. Cover the tart with parchment and fill with beans. Bake 15 minutes, remove the parchment and beans and bake another 5 minutes. Remove and allow to cool.
• Reduce the oven to 350 degrees F.
• Spread half of the cheese and half of the onions and half of the mushrooms on each tart. Bake for 15 minutes. Allow to cool 5 minutes.
• To serve, cut each tart in half length wise and then into 6 equal pieces. Arrange on a serving plate.

CARAMELIZED ONION TART

Steps:

• Remove papery outer skin from garlic (do not peel or separate cloves). Cut top off of garlic bulb. Brush with 1 tablespoon oil. Wrap bulb in heavy-duty foil. Bake at 425° for 30-35 minutes or until softened., Meanwhile, in a large skillet, cook onions and vinegar in remaining oil over medium heat for 15-20 minutes or until onions are golden brown, stirring frequently. Set aside., Cool the garlic for 10-15 minutes. Squeeze softened garlic into a food processor; add the flour, butter and salt. Cover and process until mixture resembles coarse crumbs. Press onto the bottom and up the sides of an ungreased 11-in. fluted tart pan with a removable bottom. Bake at 350° for 15 minutes., In a food processor, combine the goat cheese, eggs, parsley, salt and pepper; cover and process until blended. Sprinkle 1/2 cup Parmesan cheese into crust; top with basil. Spread goat cheese mixture into crust., Arrange onions over top; sprinkle with remaining Parmesan cheese. Bake for 25-30 minutes or until set.

CARAMELIZED ONION AND ROASTED CAULIFLOWER TART

Steps:

• 1. Preheat oven to 450F. Toss the cauliflower in the oil. Spread out onto a non stick baking sheet. Season with salt and pepper. Cook for 15, then flip. Cook 15 minutes more and remove from oven.
• 2. In a good skillet, bring 1 1/2 tbps of good olive oil to a shimmer. Add thin sliced Vidalia onions, add in a pinch or two of salt and pepper and stir, stir, stir...for about 30 minutes until they turn a beautiful golden brown. Don't ignore those fronds.
• 3. MAKE UP THAT DOUGH: I really hate working with pastry, but this was pretty harmless.
• 4. I used a whisk: Flour, cornstarch, salt and butter. Then add in the egg. I lost my pastry blender in the move to the lower 48 and had to use a fork....gave that up quick and used my grandma's fingers to get the pea sized effect I needed.
• 5. Smash that dough all together and roll it thin. Yes, I cheated and used plastic wrap as a medium. Transfer the dough to the tart pan and press in. Now lightly coat the dough with 1 TBSP Dijon mustard, bottom and sides.
• 6. Layering the Stuff: After pressing in the tart dough and brushing the bottom and sides with dijon, add in the onions. Top with cauliflower.
• 7. In a bowl, mix the eggs, marscapone, cream, white pepper, nutmeg and Guyere. Pour over the top of the tart. I had to use my hands to redistribute the cheesiness.
• 8. Top with 1/3 cup Parmesan cheese. Bake 350F for 40 minutes.

CAULIFLOWER & CARAMELIZED ONION TART

Steps:

• Position rack in center of oven; preheat to 425°F
• Toss cauliflower with 1 tablespoon olive oil in large bowl.
• Spread on large rimmed baking sheet, spacing apart.
• Sprinkle with salt and pepper.
• Roast 15 minutes; turn florets over.
• Continue roasting until tender, about 25 minutes longer.
• Cool cauliflower, then thinly slice.
• Drizzle with truffle oil; toss.
• Reduce oven temperature to 350°F.
• Press pie crust onto bottom and up sides of 9-inch-diameter tart pan with removable bottom.
• Line pie crust with foil; fill with pie weights.
• Bake crust 20 minutes.
• Remove foil and pie weights; bake until crust is golden, about 5 minutes, pressing crust with back of fork if bubbles form.
• Cool crust.
• Maintain oven temperature.
• Heat remaining 1 1/2 tablespoons olive oil in heavy large skillet over medium heat.
• Add onion; sprinkle with salt and pepper.
• Cook until onion is deep golden brown, stirring occasionally, about 40 minutes.
• Cool slightly.
• DO AHEAD Can be made 1 day ahead.
• Store crust at room temperature.
• Cover and chill cauliflower and onion separately.
• Brush bottom and sides of crust with mustard.
• Spread onion in crust.
• Arrange cauliflower evenly over.
• Set tart on rimmed baking sheet.
• Whisk eggs and next 4 ingredients in medium bowl.
• Stir in Gruyere.
• Pour mixture over filling in tart pan; sprinkle with Parmesan.
• Bake until tart is golden and center is set, about 40 minutes.
• Transfer to rack; cool 15 minutes before serving.

CARAMELIZED ONION & CHEESE TART

Steps:

• Melt butter with oil in large skillet on medium-high heat. Add onions and sugar; cook on medium-low heat 20 to 25 min. or until onions are caramelized, stirring frequently. Remove from heat.
• Heat oven to 400°F. Unroll pie crust onto baking sheet; spread with cream cheese to within 2 inches of edge. Top with blue cheese and onions. Fold edge of crust up and slightly over edge of filling.
• Bake 20 to 25 min. or until golden brown. Cool slightly. Sprinkle with chives.

CARAMELIZED ONION, WALNUT AND GORGONZOLA TART

Steps:

• Preheat oven to 375 degrees. Lightly grease a medium baking sheet. Place thawed bread dough into a large mixing bowl; add lemon juice (reserve zest for later use) and 2 tablespoons of the olive oil, working into the dough. Cover and let rise in a warm place while continuing with recipe. Heat the remaining 2 tablespoons olive oil in a large heavy skillet placed over medium heat. Add the onions, blending well. Cook until golden, stirring occasionally, about 20 to 30 minutes. Season as desired with salt and pepper. Punch down dough; remove from bowl and place on prepared baking sheet. Starting at center, press out dough with greased hands to form an approximate 11 x 10-inch rectangle. With fingers or the handle of a wooden spoon, make "dimples" in dough every 3 inches. Remove onions from skillet with a slotted spoon and cover dough with onions, distributing evenly. Bake in the preheated oven for 15 minutes. Remove from oven; sprinkle with cheese and walnuts and return to the oven for about 10 to 15 minutes more, or until the bread is lightly browned. Toss together the reserved lemon zest, arugula and the diced pear. Reserve. Remove tart from oven; cut into squares and top with pear/arugula mixture. Serve right away.