Meanwhile, for filling, in a medium bowl stir together eggs, the granulated sugar, the 3 tablespoons flour, the lemon peel, lemon juice, and half-and-half. Pour filling over hot crust. Bake for 15 to 20 minutes more or until center is set. Cool completely in pan on a wire rack. Grasping foil overhang, lift from pan. Cut into bars. Right before serving, sift powdered sugar over tops. Cover and store in the refrigerator.