Hamburger Potato Cheese Casserole

1 pound ground beef
1 medium onion, chopped
4 to 6 servings instant mashed potatoes, or use leftovers if you have them
I can Cheddar cheese soup

Brown ground beef and onion in skillet, seasoning to taste. Drain well. While beef is cooking, prepare mashed potatoes according to package directions.

 Place beef in the bottom of an oven casserole dish. Spread mashed potatoes evenly on top of beef. Spread cheddar cheese soup evenly on top of potatoes. Cover casserole and store in refrigerator until next day.

Preheat oven to 350F. Cover and bake for about 30 minutes or until heated thru and cheese is melted.