Cookie Bar:

 

2 sticks (1 cup) salted butter, softened

3/4 cup granulated sugar

1/4 cup brown sugar

1 large egg

2 teaspoons vanilla extract

2 3/4 cup all purpose flour

2 teaspoons baking powder

 

Frosting:

 

2.5 Sticks (1 1/4 cups) salted butter, softened

1 14 oz can Eagle Brand® Sweetened Condensed Milk

1/4 cup powdered sugar

1 1/2 teaspoons vanilla extract