Cheeseburger Crock-Pot Supper

Cheeseburger Crock-Pot Supper
1-1 1/2 lb ground beef
1 medium onion, coarsely chopped
1 (5 ounce) box au gratin potato mix
1 (10 ounce) can 98% fat free cream of celery soup
salt and pepper
2 tablespoons ketchup
1 tablespoon mustard
4 slices of favorite type of cheese (4 thick slices or 8 thin slices)
In a skillet, brown the ground beef with onions; drain. Place potatoes and seasoning mix in the slow cooker; cream of celery soup. Top potato mixture with ground beef and onions; salt and pepper to taste. Dot evenly with ketchup and mustard; top with cheese slices. Cover and cook on low for 4 to 6 hours. Note: Feel free to add a vegetable to this recipe. Simply add it with the soup. This recipe could use any boxed potatoes with success. Feel free to season hamburger as you would if you were making cheeseburgers.