Cream the butter, brown sugar, granulated sugar together until light and creamy. Add in the egg, vanilla extract, and peppermint extract and mix until combined.

Add in the flour, baking powder and baking soda and mix just until the dry mixture disappears.

Fold in the white chocolate chips then using a large cookie scoop out 6 equally sized cookie dough balls, place them on the prepared baking sheet and gently flatten to desired thickness.

Bake in the preheated oven for 10-12 minutes. Let the cookies cool on the baking sheet for 10 minutes before transferring to a cooling rack.

In a large bowl cream the butter, sifted powdered sugar, and peppermint extract until well combined (about 3-5 minutes).

Place the frosting in a piping bag and pipe the frosting on the cooled down cookies and enjoy! I used the Wilton 1M piping tip.