Macaroni and Cheese with Caramelized Onions and Roasted Red Bell Peppers

1 (40-ounce)  macaroni and cheese (premade or home-made version of your choice)
3/4 tablespoon butter or margarine
1 cup soft breadcrumbs
1 teaspoon granulated sugar
2 medium-sized yellow onions, halved and sliced
1 (7-ounce) jar roasted red bell peppers, chopped

1. Bake macaroni and cheese according to package directions for conventional oven, reducing cooking time to 30 minutes.
2. Melt butter in a large skillet. Remove 1 tablespoon melted butter, and combine with breadcrumbs; set breadcrumb mixture aside.
3. Cook sugar and sliced onion in remaining 2 tablespoons butter in skillet over medium-high heat, stirring occasionally, 20 minutes or until onion turns a deep caramel.
4. Remove cover from macaroni and cheese carefully. Stir in onion and chopped bell pepper. Top with breadcrumb mixture, and bake 15 more minutes.