Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large bowl, cream together the butter, granulated sugar, and brown sugar until light and fluffy.
Beat in the egg and vanilla extract until well combined.
In a separate bowl, whisk together the flour, cocoa powder, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Stir in the mint extract and chocolate chips.
Roll the dough into small balls and place them on the prepared baking sheet, spacing them a few inches apart.
Flatten each ball slightly with your fingers.
Bake the cookies for 10-12 minutes, or until set.
Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.
Enjoy!
