Preheat oven to 350°F and spray a 9x9 in pan with cooking spray
Mix crust ingredients in a bowl until thoroughly combined
Press crust into the 9 x 9 in pan
Cook for about 20 minutes, or until it begins to golden
Allow crust to cool while you prepare the filling
Whisk eggs in a large bowl
Add flour, sugar, and the juice of the lemons (about 1 cup of lemon juice), whisking until combined
Pour over crust and let bake for about 25-30 minutes (bars will continue to firm as they cool)
Remove from oven and let cool
Cut into squares and garnish with powdered sugar