Begin by adding the softened room temp butter to a large bowl. Mix it for 3 to 5 minutes. Then add in the sugar and cream those two together. Scrape the sides of the bowl as necessary.
Add in the egg, vanilla and peppermint extracts and mix until combined.
Now in a separate bowl sift or whisk together the flour, cocoa powder, salt, and baking powder.
Mix in the dry ingredients about a third at a time until well combined and you are left with a nice chocolate cookie dough.
Gather the dough into a ball and then cut the ball in half. Place a sheet of parchment paper down and roll out half of the dough on top of it until it is between 1/8th and 1/4th inch thick. You can really make them as fat or thin as you want. Then do the same with the other half of dough then stack them on top of each other.Finally, place a final piece of parchment on top. Set the stacked dough in the fridge to chill for at least an hour.
Once the dough has chilled, preheat the oven to 350 F/176C. Use a small round cookie cutter (2-inch diameter) and cut out the cookie shapes. Place them on a sheet pan lined with parchment paper or a silicone mat. Gather up the scraps of dough and roll them out, etc. The cookies won't spread so they can be placed pretty close to each other.
Bake them for 8 to 9 minutes. 8 minutes for softer cookies, 9 minutes for more crunchy cookies. Once they come out of the oven allow them to cool for a few minutes before transferring them to a wire rack to cool completely.
Next, melt your chocolate, in the microwave with bursts of 25 seconds and stirring until melted or use the double boiler method on the stovetop. Dip the cookies in the chocolate with a fork, tap off the extra chocolate and place it on the pan with the silicone mat or parchment paper. Drizzle on other colors of chocolate for a design or leave them plain. Place them in the fridge and allow the chocolate to set for 20 to 30 minutes. Enjoy!