Preheat the oven to 350 degrees. Spray a 9 x 13 pan with cooking spray and set aside.

In a large bowl cream the butter and sugar. Add in the eggs, one at a time, stirring after each addition. Stir in the vanilla.

In a small bowl combine the flour, baking powder, and salt.

Add the flour mixture to the butter mixture and mix until well combined. Stir in the sprinkles.

Bake for 25-28 minutes or until a toothpick inserted into the middle comes out clean.

Remove from oven and cool on a wire rack for 30 minutes.

Mix together the powdered sugar, vanilla, and milk. Pour over top of the cookie bars and spread evenly. Sprinkle on the sprinkles.

Allow the glaze to harden for 30 minutes. Cut into 18 bars.