100 cal Lemon Bars!!

SO just had a sudden Lemon Bar craving, and was browsing google and stumbled upon this recipe. Haven't tried it, but it looks alright haha.
http://www.fitnessmagazine.com/recipes/desserts/low-calorie/low-fat-lemon-bars/
Slim Lemon Squares

Makes: 16 servings

Ingredients
Nonstick cooking spray
3/4 cup all-purpose flour plus 2 tablespoons
2/3 cup granulated sugar plus 3 tablespoons
1/2 stick cold butter, cut into 1/2-inch cubes
1 egg
1 egg white
1/4 teaspoon finely grated lemon zest
2 tablespoons lemon juice
1 tablespoon water
1/4 teaspoon baking powder
1 tablespoon powdered sugar

Directions
1. Coat an 8-x-8-x-2-inch baking pan with nonstick spray; set pan aside.
2. In a small mixing bowl, combine 3/4 cup flour and 3 tablespoons sugar; cut in butter until crumbly. Pat mixture onto the bottom of prepared pan. Bake in a preheated 350-degree oven for 15 minutes.
3. Meanwhile, in the same bowl, combine egg and egg white. Beat with an electric mixer on medium speed until frothy. Add remaining sugar and flour, lemon zest, lemon juice, 1 tablespoon water, and baking powder. Beat on medium 3 minutes or until slightly thickened. Pour mixture over baked layer in pan. Bake 20 to 25 minutes more or until edges are light brown and center is set. Cool in pan on a wire rack.
4. Sift powdered sugar over top. Cut into 16 bars. Store in refrigerator.

Nutrition facts per serving (1 bar): 100 calories, 1g protein, 17g carbohydrate, 3g fat (2g saturated), 0g fiber
Healthy Baking Tips


I bet a bunch of other things (butter, sugar, although this recipe calls for less than most) could be substituted to make it even healthier, knock yourselves out. I'd try but I cannot bake at all.