Preheat your oven to 350°F (175°C).
In a large bowl, mix the cream of chicken soup, sour cream, milk, garlic powder, onion powder, salt, and pepper.
Add the chopped cooked chicken and shredded cheddar cheese to the mixture. Stir until well combined.
Pour the mixture into a greased 9x13-inch baking dish and spread evenly.
In a separate bowl, combine the crushed Ritz crackers with melted butter.
Sprinkle the cracker topping evenly over the casserole.
Bake for 25–30 minutes, or until bubbly and golden on top.
Serve hot and enjoy!