Easy Lemon Bars

It is Father's Day today, and although my own dad passed away this year, I can still honor and celebrate my sweetheart.  One of his favorite treats is lemon bars, so this will be our dessert tonight.
I found this recipe one rockrecipes.com.
For the crust:

• 1 cup cold butter, cut in small pieces
• 1/2 cup sugar
• 2 cups flour 

Cut butter into sugar and flour with a food processor or pastry blender.  It will be powdery.  Grease the bottom of a 13 x 9 baking pan.  Press the dough firmly into the bottom of the pan.  Bake at 350 degrees (or 325 degrees for a glass pan) for 20 minutes.

For the lemon layer

• 1 1/2 cups sugar
• 1/4 cup flour
• 4 eggs
• zest of two lemons, very finely chopped
• juice of 2 lemons, about 2/3 to 3/4 cup juice 

Whisk all ingredients together well until the sugar is dissolved and the egg whites are fully mixed.  Let sit for 10 minutes.  When the crust comes out of the oven, whisk lemon mixture well one more time and then pour over the hot crust.  Return to the oven and bake an additional 20-25 minutes.  Cool completely.  Sprinkle with powdered sugar.