Moore Family Potato Casserole

1 stick butter
8 oz pkg cream cheese
2 cans undiluted cream of celery soup
1 sm onion chopped
8 oz cheddar cheese, shredded
24 oz bag frozen hash brown potatoes

Melt butter in saucepan. Add onions, saute until softened. Add soup and cream cheese and stir until cheese melts and thick sauce forms. In 9 x 13 pan, greased, put 1/2 potatoes, top with 1/2 sauce and 1/2 cheddar cheese. Layer remaining ingredients. Bake 350 1 hour uncovered. May need to adjust cooking time if using a casserole dish.