Grandma Long's Tatertot Casserole

From the Kitchen of: Grandma Long

INGREDIENTS
1 lb hamburger browned and drained
½ onion chopped
1 can cream of celery soup
2 cups grated mozzarella cheese
1 package frozen tatertots, thawed

INSTRUCTIONS
Preheat oven to 400 degrees. Brown hamburger and drain. Combine hamburger, onion, and celery soup with ½ can water in large saucepan. Warm through and mix with tatertots. Pour in casserole dish and top with cheese. Cover with foil and bake at 400 for about 1 hour or till heated.