Grease 1 1/2 qt shallow baking dish.
Thoroughly combine chex & butter. Set aside.
Combine potatoes, sour cream, onion powder, salt, pepper, & broccoli. Stir gently until well mixed. Spread half of mixture in baking dish. Sprinkle with half of cheese, then half of crumbs. Repeat.
Bake in 350°F oven for 25 minutes or until crumbs are golden.