From: http://www.melskitchencafe.com/sugar-cookie-bars/ SUGAR COOKIE BARS INGREDIENTS Bars: ¾ cup salted butter, softened to cool room temperature ¾ cup granulated sugar ¼ cup powdered sugar 2 large eggs 1 teaspoon vanilla extract ½ tablespoon fresh lemon zest, (optional) 2 ¼ cups all-purpose flour 1 teaspoon baking powder ½ teaspoon salt Frosting: 6 tablespoons salted butter, softened 2 ½ cups (285 g) powdered sugar 3 tablespoons milk or cream ¼ teaspoon vanilla extract Sprinkles, optional INSTRUCTIONS Preheat oven to 375 degrees F. For the bars, in a large bowl, cream together the butter, granulated sugar and powdered sugar until light and fluffy. Add the eggs and vanilla and mix for 1-2 minutes. Stir in the lemon zest (optional), flour, baking powder and salt. Mix until combined. Lightly grease a 9X13-inch baking pan with cooking spray or line with parchment paper and grease. Press the sugar cookie dough into an even layer in the bottom of the pan. Bake for 10-13 m...