Cream together crust ingredients like pie crust and pat into a 9" x 13" pan. Bake 15 to 20 minutes at 350°F.; set aside. Mix together the dry topping ingredients; add eggs and lemonade and mix well. Pour over baked crust. Bake 25 to 30 minutes at 350°F. When slightly cool, dust with powdered sugar. Cut into bars while still warm.