Carman's Caper

1 1/2 lbs ground beef
1/2 cup chopped onion
1 1/2 tsp salt
1/4 tsp pepper
1/2 lbs spaghetti
19oz canned tomatoes
10oz condensed cream of mushroom
1 cup grated cheddar cheese

Brown beef and onion in frying pan. Sprinkle with salt and pepper; stir. Transfer to bottom of 2 qt casserole. Cook spaghetti according to package directions; drain. Layer over meat. Break up large tomato chunks; pour over top. Spoon soup over tomatoes. Cover with cheese. Bake uncovered in 350F oven for 30 minutes until hot and cheese is melted. Cover halfway through cooking if cheese gets too dry.