Mix crust and press into 9x13” baking pan.
Bake at 350° for 20 min.
Meanwhile, in small bowl beat eggs until light.
Gradually add sugar beat until mixture is thick and lemon-colored.
Add lemon zest, juice, and remaining 1/3 c. flour, and baking powder.
Pour lemon mixture over baked crust and return to oven, bake for 15 to 20 min, or until topping is pale golden.
Place on a rack to cool. While still warm sift powdered sugar lightly over top.
Cut in 2 ½ in. bars. Store in airtight container.