Cookie Bars • 1 cup unsalted butter softened (226g) • 2 oz cream cheese softened (57g) • 1 ¾ cup granulated sugar (350g) • 2 large eggs • 1 large egg yolk • 1 teaspoon vanilla extract • 2 ½ cups all-purpose flour (285g) • ½ teaspoon baking powder • 1 teaspoon table salt

Frosting • 10 Tbsp unsalted butter softened (141g) • 2 oz cream cheese softened (57g)  • 2 cups powdered sugar (250g) • 1 Tbsp cornstarch  • ½ teaspoon vanilla extract • ⅛ teaspoon table salt • Sprinkles for decoration optional

Combine butter, cream cheese, and granulated sugar in a large bowl and use an electric mixer (or a stand mixer) to beat until creamy and well-combined.

Add eggs, egg yolk, and  vanilla extract and stir until completely combined.

In a separate bowl,  whisk together flour, baking powder, and salt.

With mixer on low-speed, gradually add flour mixture to the butter mixture until completely combined.

Preheat oven to 350F (175C) and lightly grease a 13×9” (33x23cm) baking pan with baking spray or butter.

Spread batter evenly into prepared baking pan and bake on 350F (175C) for 25-30 minutes or until the edges are beginning to turn golden brown.

 Remove from the oven and use a toothpick to test to make sure center is set. Allow to cool completely before covering with frosting.

While the pan is cooling make your frosting. Combine butter and cream cheese and beat with an electric mixer until completely smooth and creamy.

With mixer on low-speed, gradually add powdered sugar until completely combined, then stir in cornstarch.

With mixer on low-speed, add half of the powdered sugar, cornstarch, vanilla extract and salt. 

Gradually add remaining powdered sugar and mix until completely combined

Spread frosting evenly over completely cooled cookie bars and add sprinkles on top if desired.

Slice, serve and enjoy!