WHITE FISH POT PIE

Steps:

• Preheat the oven to 425 degrees F (220 degrees C).
• Cut pastry into 6 rectangles and place on a baking sheet.
• Bake in the preheated oven until puffed and golden, 15 to 20 minutes. Remove from the oven; leave the oven on.
• Meanwhile, cut mahi mahi into 1 inch pieces. Season with a pinch of salt and pepper.
• Heat olive oil in a large pot or Dutch oven over medium heat. Add potato, celery, and carrot. Cook, stirring occasionally, until just tender, about 8 minutes. Add leeks and let soften, about 3 minutes. Add garlic and cook until fragrant, about 30 seconds. Add butter.
• When butter has melted, add flour and whisk for 1 minute. Slowly whisk in milk and water, then add 1 teaspoon salt and 1/2 teaspoon pepper. Bring to a boil.
• Reduce heat to a simmer, and cook until mixture thickens slightly, 3 to 4 minutes. Whisk in sour cream, lemon juice, and Dijon. Add fish and cook over low heat until fish flakes easily with a fork, 7 to 8 minutes. Stir in parsley and chives and remove from the heat.
• Transfer fish mixture to a 2-quart pastry dish. Place pastry rectangles on top, and brush each one with beaten egg.
• Return to the oven and bake until pastry is puffed and golden brown and filling is bubbly, about 10 minutes. Let stand for 5 minutes before serving.