Warm the oven to 350°F and line two baking sheets with parchment.
Cream the butter with both sugars in a large bowl using an electric mixer until the mixture turns light and aerated.
Blend in the egg yolks, peppermint extract, and vanilla, mixing until the batter becomes pale and fluffy.
Stir in the flour, cocoa powder, baking powder, baking soda, and salt until the dough comes together smoothly.
Fold in the peppermint chips and chocolate chips just until evenly distributed.
Portion the dough into 20 scoops and arrange them spaced apart on the prepared pans.
Bake for 10–12 minutes depending on desired texture.
Allow cookies to rest on the baking trays for 2 minutes, transfer to a rack for 10 minutes, then top with crushed candy canes if desired.
Notes
These cookies bring together nostalgic holiday flavors with an indulgent chocolate base. Their soft, chewy centers make them perfect for cozy winter moments. Enjoy them warm with a mug of something comforting.