In a medium bowl, combine the chicken, rice, broccoli, cream of chicken soup, cheddar cheese soup, sour cream, butter, garlic powder, and onion powder. Mix until all ingredients are thoroughly combined.
Pour the mixture into a 9x13 inch baking dish.
Sprinkle the cheddar cheese and crushed cornflakes over the top of the casserole.
Bake in preheated oven for 30 minutes, or until cheese is melted and bubbly.
Interesting Facts
Chicken-Broccoli-and-Rice Casserole is a great way to get your family to eat more vegetables.
This casserole can be frozen and reheated for a quick and easy meal.
This casserole can also be made with any type of cooked meat, such as turkey, ham, or beef.