Leftover Turkey Pot Pie Casserole is an easy dinner using your leftover Thanksgiving turkey. Carrots, peas, mushrooms, and celery together in a seasoned sauce and baked with a flakey gluten free pie crust. It's the flavor of pot pie, with the ease of a casserole!
Preheat oven to 375°F. Grease a 9x13" casserole dish.
In a large pot over medium heat, melt butter and olive oil together. Sauté onions until translucent, about 5 minutes.
Whisk together flour, onion powder, celery seed, salt, and pepper. Add flour to onions, stirring continuously. Pour in chicken broth and milk. Keep stirring while sauce thickens, about 2-3 minutes.
Add vegetables and turkey to mixture and stir together completely. Pour mixture into casserole dish.
Lay pie crust over casserole, trimming the edges. Bake for 30-40 minutes, or until crust is golden brown.
*You can lay the pie crust in any pattern you'd like!
*If you want the crust to be really golden brown, whisk together 1 egg and 2 tbsp water and brush lightly over pie crust before baking.