In a large mixing bowl, combine the cooked turkey, cooked pasta, frozen peas, shredded cheddar cheese, cream of mushroom soup, milk, garlic powder, and onion powder. Mix well.
Season with salt and pepper to taste.
Transfer the mixture to a baking dish and spread it out evenly.
Bake in the preheated oven for 30 minutes, or until the casserole is bubbly and the top is golden brown.
Let it cool for a few minutes before serving. Enjoy!
Notes:
This casserole is a great way to use up leftover turkey.