Recipe for Flounder Casserole

2 pounds boneless fish fillets
2 cans condensed cream of celery soup
3 cups milk
10 small potatoes peeled and halved
7 tablespoons diced ham
5 tablespoons diced onion
6 slices American Cheese
4 tablespoons grated mozzarella cheese

Coat inside of two-quart casserole dish lightly with oil then lay in fillets. Place potatoes along the sides. In a saucepan heat and mix soup, milk, onions and ham, then pour over fillets and potatoes. Sprinkle on the grated cheese and bake in a 200 F oven for three hours. Lay cheese slices on top and heat until melted.
Any type of fish will work for this recipe.