Another one we like is a Cheeseburger Macaroni Skillet Casserole

Prepare 1 pkg macaroni and cheese according to directions.
Brown 1 lb ground beef. Add chopped onion if you like. Drain grease. Add 16 oz pkg frozen mixed vegetables. Stir-fry about 7 minutes until crisp-tender. Then add 1/2 c. ketchup, 1 Tbsp mustard, 1/4 tsp garlic powder, 1/4 c. water. When heated through, add 1/2 cup shredded cheddar cheese and prepared macaroni and cheese. Enjoy.

You can play with the seasonings to your taste.