Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper.
In a bowl, whisk together the gluten-free flour, cocoa powder, baking soda, and salt.
In another bowl, beat the softened butter, brown sugar, and granulated sugar until creamy.
Add the vanilla extract, peppermint extract, and egg to the butter mixture. Beat until combined.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Fold in the chocolate chips.
Drop spoonfuls of dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake for 10 minutes or until the edges are set. Let the cookies cool on the baking sheet for 5 minutes before transferring to a cooling rack.