Preheat the oven to 375 degrees F (190 degrees
C). Grease a 9×13 inch pan.
In a medium bowl, stir together 1 cup sugar, 3
cups flour, baking powder, salt, and lemon zest.
Use a fork or pastry cutter to blend in the
butter and egg. Dough will be crumbly. Pat half
of dough into the prepared pan.