Preheat the oven to 400°F
Prepare a pie dish or baking dish
Cook diced chicken, turkey, or vegetables in a skillet
Add chopped onions, carrots, celery, and peas
Stir in butter and flour to make a thickening base
Add broth and milk or cream
Season with salt, pepper, garlic, and herbs
Simmer until the filling is thick
Place one pie crust in the dish
Pour the filling into the crust
Cover with a second pie crust or puff pastry
Cut slits in the top crust
Seal the edges of the crust
Brush the top with egg wash if desired
Bake for 30 to 40 minutes
Bake until the crust is golden brown and the filling is bubbling
Let cool for 10 to 15 minutes before serving