Broccoli Rice Casserole - Love of Food

Ingredients

• 1 tablespoon butter
• 1 cup onion, finely chopped
• 1 cup cooked white rice
• 1 10-ounce package frozen broccoli florets, thawed and drained
• 1 - 12.25 ounce can cream of mushroom soup
• 1⁄2 cup Cheese Whiz®