Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.
In a large mixing bowl, cream the softened butter and granulated sugar together until light and fluffy, about 3-5 minutes.
Beat in the egg, vanilla extract, and peppermint extract until well combined.
Gradually add the dry ingredients to the butter mixture, mixing until a dough forms.
Divide the dough in half. In one half, mix in the crushed peppermint candies.
Add a few drops of red gel food coloring to the other half of the dough and mix until you achieve a vibrant red color. You can add green if desired for added contrast.
Take about 1 tablespoon of each dough and roll them into a small ball. Press the red and peppermint dough balls together, and then gently roll them to form a single swirl.
Place the prepared cookie dough balls onto the lined baking sheet, leaving about 2 inches of space in between each cookie.
Bake in the preheated oven for 10-12 minutes or until the edges are lightly golden. The cookies will look a bit soft but will harden as they cool.
Remove from the oven and allow to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.
Optional: Once cooled, dust the cookies with powdered sugar for an extra festive touch.
Notes
Optional: Dust with powdered sugar for a festive touch.