Party Potatoes
["5 lb. potatoes", "1 onion", "butter", "salt", "pepper", "2 1/2 pt. whipping cream or half and half"]
["Cook potatoes day before and cool in refrigerator overnight. Grate potatoes and onion; dot with butter and salt and pepper. Cover with plastic wrap to store overnight.", "Before placing in oven, add whipping cream or half and half.", "Place in a 9 x 13-inch pan and bake at 350\u00b0 for 55 minutes."]
["potatoes", "onion", "butter", "salt", "pepper", "whipping cream"]