From the Campbell's Classic Recipes cookbook. Quick, easy, cheap, and my kids love it.
1 pound ground beef
1 medium onion, chopped
1 can (10 3/4 oz) Campbell's Condensed Tomato Soup
1/4 cup water
1 tablespoon Worcestershire sauce
1/2 cup shredded cheddar cheese
2 cups cooked corkscrew macaroni (about 1 1/2 cups uncooked), or you could use elbow macaroni
In medium skillet over medium-high heat, cook beef and onion until beef is browned, drain if necessary. Add soup, water, Worcestershire sauce, cheese and macaroni. Reduce heat to low and heat through.