Buttercream Frosted Sugar Cookie Bars

•1 ⅔ cups all purpose flour-210 grams
•¾ teaspoon baking powder
•Heaping ½ teaspoon fine salt
•½ cup unsalted butter, softened
•½ cup + 2 Tablespoons sugar-130 grams
•3 Tablespoons brown sugar-40 grams
•1 teaspoon lemon or orange zest
•1 large egg, room temp
•2 Tablespoons vegetable/coconut oil
•2 teaspoons vanilla
FROSTING
•6 Tablespoons unsalted butter, softened
•1 ¼ cups powdered sugar
•Pinch fine salt
•1 teaspoon vanilla
•2-4 teaspoons milk or water

1. Preheat your oven to 350*F. Grease an 8” square pan lightly with baking spray and line bottom with parchment.
2. Whisk together flour, baking powder and salt in a medium bowl and set aside.
   
3. Combine butter, sugars and zest in your mixer bowl and mix on medium speed until fluffy, 3-4 minutes.
4. Add the vanilla, egg and oil and mix again on medium until well combined and fluffy. Scrape bowl.
5. Add the dry ingredients and mix just to combine, mixing in remaining flour with a spatula.
6. Transfer the dough to the prepared pan and press into place. Wet your fingers with cold water to prevent the dough from sticking to your hands.
7. Bake for 23-26 minutes or until golden on the edges and top and set in center. The cookie will puff but will settle when finished baking. Cool completely before removing from the pan and frosting.
8. Make the buttercream by beating the butter in your mixer bowl until very smooth and shiny, 2-3 minutes. If the butter is too stiff, microwave the butter for 4-5 seconds and mix again.
9. Add the powdered sugar and salt and mix on low until combined. Scrape the bowl then add the vanilla and 2 teaspoons milk.
10. Mix on low to combine and then beat on high speed for 3 minutes. Scrape the bowl and check to see if the frosting is spreadable- if it is too thick add additional milk and mix again on high for another minute.
11. Transfer the buttercream to the center of the bar cookie and spread smooth to the edges. Top with sprinkles if desired before slicing.