WARM SPINACH SALAD WITH SHIITAKE MUSHROOMS AND RED ONION

Warm Spinach Salad with Shiitake Mushrooms and Red Onion image

Provided by Martha Stewart

Time 55m

Yield Serves 10 to 12

Number Of Ingredients 8

1/2 cup white balsamic vinegar
2 teaspoons sugar
Kosher salt and freshly ground pepper
1 small red onion, thinly sliced into rounds (1 cup)
2 pounds spinach (from 3 large bunches), tough stems removed, thoroughly washed and drained
1/2 cup extra-virgin olive oil
1 pound shiitake mushrooms, stemmed and halved, or sliced if large
1/4 cup sesame seeds, toasted

Steps:

In a saucepan, bring vinegar, sugar, and 1 teaspoon salt to a simmer. Remove from heat; stir in onion. Let cool completely. If desired, refrigerate in an airtight container up to 1 week. Drain, reserving onion and 1/3 cup liquid.
Place spinach in a large bowl. In a large straight-sided skillet or shallow pot, heat 1/4 cup oil over medium-high. Add mushrooms, season with salt and pepper, and cook, stirring occasionally, until tender and golden brown in places, about 15 minutes. Add about one-quarter of spinach and cook just until collapsed, about 1 minute. Immediately spoon mushroom mixture over spinach in bowl; add reserved pickled onion and pickling liquid, remaining 1/4 cup oil, and sesame seeds. Toss to evenly coat. Season with salt and pepper; serve.