By hand, mix the softened butter and confectioners' sugar until thoroughly mixed. Add the flour and cornstarch and knead in ... in tightly covered container.
Ingredients: 5 (cornstarch .. flour .. sugar .. temperature ...)
Because this is a large ... process half the butter until creamy. Add half a cup of sugar, process until blended. Add 2 cups flour and process with a quick ... cut while still hot.