Crust: Combine the flour, powdered sugar and butter; mix thoroughly. Press into a 10 x 15 inch pan. Bake at 350°F for 8-15 minutes, til lightly brown.

Topping: Mix together eggs, sugar, lemon juice and zest. Spread over the baked crust. Return to 350° oven for another 20-25 minutes until filling is set and lightly browned. Cool before cutting.