Cream together butter, peanut butter and brown sugar in the bowl of a stand mixer until light and fluffy. Mix in the eggs one at a time until combined.

In a separate bowl, sift together gluten-free flour, xanthan gum, baking soda and salt. Mix into the butter mixture until combined. Cover dough with plastic wrap and refrigerate for one hour or up to 48 hours. Un-wrap chocolate kisses while dough is chilling.

Pre-heat oven to 375°F and line a baking sheet with parchment paper or silicon baking mat. Scoop 1 ½ tablespoons of dough onto prepared baking sheets and bake for 8-10 minutes.

Place a chocolate kiss on each cookie immediately after removing cookies from the oven. Cool 5 minutes on the baking sheet until moving to a cooling rack.