Cook and mash 5 lbs. of potatoes; add 8 oz. cream cheese, 8 oz. sour cream, 1/4 cup butter, and 1/4 cup of milk. Beat until evenly mixed and then refrigerate until ready to reheat. Reheat, covered, in a 350 degrees oven for 45 minutes or until hot; or heat in slow cooker for 4 to 6 hours. view more.