Mary'S Potato Casserole
["6 medium potatoes", "1 (16 oz.) sour cream", "2 sticks margarine", "1 medium onion, chopped", "1 1/2 c. grated Cheddar cheese"]
["Boil potatoes with skins on. Cool. Peel and grate potatoes. Add melted margarine, sour cream, chopped onion and grated cheese. Put in casserole dishes and bake at 350\u00b0 for 30 minutes. Sprinkle grated cheese over top and put back in oven until cheese is melted."]
["potatoes", "sour cream", "margarine", "onion", "Cheddar cheese"]