Step 1

Preheat oven to 350°F. Spray a 13- x 9-in. pan with cooking spray and line parchment paper, letting the long edges hang over the sides of the pan slightly.

Step 2

Whisk together flour, baking powder, and salt in a medium bowl.

Step 3

In a large bowl, combine butter and sugar. Beat with an electric mixer at medium speed until fluffy and combined for about 2 minutes. 


Add egg, milk, and vanilla; beat until smooth. 
Gradually add flour, mixing at medium to low speed. Continue to mix only until a smooth, soft dough forms.

Step 4

Press dough into an even layer in the prepared pan.

Step 5

Bake for 22-25 minutes or until cookie bars are golden brown on the edges, the center is set, and a toothpick inserted into the center comes clean. Cool completely in the pan on a cooling rack for about 1 1/2 hours.

Step 6

In a large bowl, beat butter and salt with an electric mixer at medium speed until the butter is smooth and light, for about 1 minute. Add powdered sugar and mix until smooth. Add milk, vanilla, and almond extract (if using); beat until evenly combined and fluffy, about 2-3 minutes. Add food color, if using, until the desired color is reached, beating until smooth and combined.

Step 7

Remove the cookie bars from the pan using the parchment paper as handles. 
Spread icing on top of cooled cookie bars. 
Sprinkle with sprinkles if using. Cut into squares to serve.