Brown beat and onions. Drain extra fat. Put in large bowl. Add corn, soup, salt, pepper and ketchup to meat and mix.
Cook noodles, drain. Combine with meat, mix. Put into 3-quart casserole. Sprinkle cheese over top. Cover and bake at 350ยบ for 45 minutes. Remove cover and bake until cheese is melted and bubbly.