1. Heat oven to 350 degrees. Grease 13x9 inch baking dish.
2. Melt 2 tablespoons butter in a large pan over medium-high heat. Cook onion in butter, stirring occasionally, until tender; reduce heat to medium. Stir in cheese, soup, milk, and pepper. Cook, stirring frequently, until cheese is melted.
3. Stir in broccoli and rice. Spoon into baking dish. Mix bread crumbs and 2 tablespoons melted butter; sprinkle over rice mixture. Bake uncovered 30 to 35 minutes or until light brown on top and bubbly around edges.