Also known as (AKA) cheesy potatoes:
1 2lb. bag of hash brown potatoes
1 stick margarine
1 lg. pkg. mozzarella cheese
1/2 c. chopped onion
1 c. sour cream
1 can cream of chicken soup
1 small can French Fried Onions (if desired)
Mix all ingredients except fried onions. Put in 9 X 11 pan. bake at 350 degrees for 45 minutes. Last 5 minutes, sprinkle fried onions on top. Enjoy!