1Preheat the oven to 375 degrees F (190 degrees C).
2Whip butter with an electric mixer until fluffy. Stir in the confectioners' sugar, cornstarch, and flour. Beat on low for one minute, then on high for 3 to 4 minutes. Drop cookies by spoonfuls 2 inches apart on an ungreased cookie sheet.
3Bake for 12 to 15 minutes in the preheated oven. Watch that the edges don't brown too much. Cool on wire racks.
Footnotes
Tip
Aluminum foil can be used to keep food moist, cook it evenly, and make clean-up easier.