1/2 cup butter, softened
Generous 1/2 cup sugar
Scant 1 cup cornstarch
1/2 cup margarine, softened
1 2/3 cups all-purpose flour
Blend well with hands. Press into a 13 x 9-inch glass baking dish. With fork, poke holes everywhere. Every inch must be perforated several times with holes that go to the bottom of the pan.
Bake at 325 degrees F for 25 to 35 minutes, until golden brown.
Let cool for 5 to 10 minutes before slicing into bars.