Stir the soup, milk, mustard, broccoli and cheese in a 1 1/2-quart casserole.
Stir the bread crumbs and butter in a small bowl. Sprinkle the crumb mixture over the broccoli mixture.
Bake at 350 degrees F for 30 minutes or until the mixture is hot and bubbling.
Rice Is Nice: Add 2 cups cooked white rice to the broccoli mixture before baking.
Cheese Change-Up: Substitute mozzarella cheese for the Cheddar.