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

In a large bowl cream together the butter and sugar until fluffy.

Add in the egg and vanilla and mix until combined.

Add in the flour, salt, and baking powder. Mix until a cookie dough forms.

Mix in the peppermint crunch chips.

Spread the batter into the prepared pan and bake for 30-35 minutes or until the top is golden brown.

Remove from oven and cool on a wire rack.

To make the frosting put the butter in a large bowl and use a hand mixer to mix the butter until creamy.

Add in the powdered sugar, vanilla, peppermint extract, and milk. Beat on low speed until the frosting is combined then increase speed to medium high and beat for 1-2 minutes or until fluffy and smooth.

Frost the bars with the frosting and sprinkle with candy cane finishing sugar.

Cut into 24 bars and serve.