In large bowl, mix flour with 1/2 cup powdered sugar; cut butter into flour mixture until crumbly. Press into an ungreased 13"x9" baking pan. Bake at 350° F. about 20 minutes until set and edges just begin to look golden brown. Remove from oven and set aside to cool.
Meantime, turn oven down to 325° and beat eggs on high for two minutes; turn beater down to medium speed and add granulated sugar and lemon juice. Add a few drops of yellow food coloring if desired; pour over crust. Bake at 325° F. for 25 minutes; cool.
Allow bars to cool. Sprinkle top with powdered sugar and cut into bars.
*Notes: I made a meringue on the bars in the picture instead of the powdered sugar topping and baked for a few minutes longer to set so it looks just a bit different, than it would look if you made these exactly, according to the recipe directions.