Preheat oven to 325 degrees. Have ready a 9-inch square baking pan. In large bowl, mix 1/2 cup all-purpose flour, whole wheat flour, confectioners’ Sugar and margarine until crumbly. Press mixture into ungreased pan. Bake 10 to 15 minutes, until lightly golden. Remove from oven. In small bowl using electric mixer, beat egg, egg Replacer or tofu, granulated sugar, orange juice concentrate and lemon juice until pale and well blended. Beat in remaining 2 tablespoons all-purpose flour, lemon peel and baking powder.