adapted from the Betty Crocker Cookbook
Mix flour, butter, and 1/4 cup powdered sugar. Press in an ungreased square pan, 8×8 or 9×9, building up 1/2 inch edges. Bake for 20 minutes at 350F. Remove from oven.
Beat granulated sugar, lemon zest, lemon juice, baking powder, salt, and eggs with electric mixer on high speed about 3 minutes or until light and fluffy. Pour over hot crust.
Bake 25-30 minutes or until no indentation remains when touched lightly in center. Cool in pan on wire rack. Dust with powdered sugar.