Posted on January 18, 2020January 18, 2020 In this recipe for make-ahead mashed potatoes, cream cheese, sour cream and butter combine to make this rich and delicious casserole perfect to serve along side meat, poultry or fish. In this recipe for make-ahead mashed potatoes, cream cheese, sour cream and butter combine to make this rich and delicious casserole perfect to serve along side meat, poultry or fish.