Preheat your oven to 375°F and lightly butter a 9x13-inch baking dish. Place the frozen pie crust on your counter to thaw while you prepare the filling—this saves the frustrating cracks that happen when crusts are too cold.

Melt 4 tablespoons butter in a large skillet over medium heat, then add your diced onion and minced garlic. Sauté for 3-4 minutes until the onion becomes translucent and fragrant, stirring occasionally to prevent burning and ensure even cooking.

Sprinkle the 3 tablespoons of flour directly over the vegetables and stir constantly for 1-2 minutes to create a roux base. This prevents lumpy sauce and builds the flavor foundation for your thanksgiving leftover turkey pot pie family recipe that everyone will adore.

Gradually pour in the 2 cups chicken broth while whisking continuously to prevent lumps from forming in your sauce. Add the 1 cup heavy cream, dried thyme, and dried sage, then season with salt and pepper to taste—simmer for 5 minutes.

Fold in your shredded turkey, frozen peas, diced carrots, and diced celery gently to avoid breaking up the tender poultry pieces. Transfer this creamy turkey filling to your prepared baking dish and smooth the top so it cooks evenly.

Arrange the thawed pie crust over the filling, pressing edges gently against the dish sides for a sealed appearance. Brush the entire crust surface with the beaten egg, which creates that beautiful golden-brown finish bakers chase.

Bake for 40-45 minutes until the crust turns deep golden brown and the filling bubbles slightly at the edges. Let rest 5 minutes before serving so the filling sets properly and your family can eat without burning their mouths.