Preheat your oven: Preheat your oven to 350°F (175°C).
Cook the pasta: In a large pot, bring salted water to a boil. Add 2 cups of pasta and cook according to package instructions until al dente. Drain and set aside.
Prepare the turkey: In a mixing bowl, combine 1 pound of cooked turkey with 1 cup of broccoli florets, 1 cup of shredded cheddar cheese, and 1 cup of shredded mozzarella cheese.
Create the creamy sauce: In another bowl, mix 1 cup of cream of chicken soup, 1 cup of sour cream, and 1/2 cup of milk. Add 1 teaspoon of garlic powder, 1 teaspoon of onion powder, 1 teaspoon of salt, and 1/2 teaspoon of black pepper. Mix until well combined.
Combine the ingredients: In a large mixing bowl, combine the cooked pasta, turkey mixture, and the creamy sauce. Stir until everything is evenly coated.
Transfer to baking dish: Pour the mixture into a greased 9x13-inch baking dish, spreading it evenly.
Add the topping: In a small bowl, mix 1 cup of breadcrumbs with 2 tablespoons of melted butter. Sprinkle this mixture evenly over the top of the casserole.
Bake: Place the casserole in the preheated oven and bake for 30-35 minutes, or until the top is golden brown and the casserole is bubbling.
Cool and serve: Once finished, let it cool for a few minutes before serving. Enjoy your cheesy turkey casserole hot!