Using a hand mixer on medium low speed and a large bowl, cream the butter and sugars until light and fluffy.
½ cup unsalted butter, ½ cup light brown sugar, ½ cup granulated sugar
Add the egg and peppermint extract, mixing until smooth and fully combined.
1 large egg , 1 teaspoon peppermint extract
In a separate bowl, whisk together the flour, cocoa powder, baking soda, and salt.
1 cup all-purpose flour, ½ cup unsweetened cocoa powder, ¼ teaspoon baking soda, ½ teaspoon salt
Slowly add the dry ingredients to the wet mixture, stirring just until combined.
Fold in the chocolate chips with a spatula so they are evenly distributed.
1 cup semi-sweet chocolate chips
Cover the cookie dough and chill in the refrigerator for 30 minutes.
Preheat the oven to 375 degrees and line two parchment lined baking sheets.
Scoop the dough using a cookie scoop and roll into golf ball sized portions.
Roll each cookie dough ball in crushed candy canes until coated and place on the baking sheet a few inches apart.
½ cup crushed candy canes or peppermint candies
Bake for 9 to 11 minutes until the edges are set and centers remain soft.
Cool on the baking sheet for 5 minutes, then transfer to a cooling rack.