Nonstick cooking spray
1/4 cup unsalted butter, softened at room temperature
1/4 cup granulated sugar
1 cup flour
1/4 teaspoon salt
1/2 teaspoon grated lemon zest
1 whole egg
2 egg whites
1 cup granulated sugar
1 teaspoon flour
1/2 teaspoon baking powder
1/3 cup lemon juice, freshly squeezed (about 2 juicy lemons)
1 teaspoon grated lemon zest
Confectioner’s (powdered) sugar for dusting
Preheat oven to 350° F. Coat an 8-by-8-inch pan with cooking spray. For crust: Cream together butter and sugar; add flour, salt and lemon zest. Beat until crumbly and pat into pan. Bake for 18–20 minutes or until golden. Remove from oven; let cool.
While crust is baking, prepare the topping: Whisk egg and egg whites until frothy. Add sugar, flour, baking powder, lemon juice and lemon zest; mix until combined. Pour mixture over crust and bake for an additional 25 minutes or until topping is set and slightly golden. Cool on a wire rack; dust with confectioner’s sugar and cut into 16 2-inch squares. Refrigerate if not serving immediately. Serves 8.
Nutritional information per serving (2 squares): 250 calories, 25% fat (7 grams), 70% carbohydrate, 5% protein, .5 gram fiber, 1 milligram iron, 20 milligrams calcium, 32 micrograms folate.