Lighter Lemon Bars - Master recipes

Ingredients

• Nonstick cooking spray -
• 1 c. all-purpose flour -
• 1/2 c. powdered sugar -
• 1/2 tsp. baking powder -
• 1/4 tsp. salt -
• 3 tbsp. light butter -
• 2 tbsp. ice water -
• 4 large egg whites -
• 1 large egg -
• 1/2 c. freshly squeezed lemon juice -
• 2 tsp. finely grated lemon zest -
• 1 c. granulated sugar -
• 1 tbsp. whole wheat flour -