1 lb. butter
1 lb. rice flour (or 4 c. wheat flour sifted with 1/2 c. cornstarch)
1/4 lb. confectioners' sugar

Preheat oven to 300 degrees.

Cream butter and sugar until smooth; cream in flour until fully blended (should be the texture of pastry dough). Press into round or square cake pan to a depth of 1". Bake in a slow oven for 1 1/2 hours or until firm and very slightly brown. Do not overbake or the shortbread will have a burned flavor. Immediately upon removal from the oven, cut into wedges or squares. Let shortbread cool completely before removing pieces from the pans.