Preheat oven to 350 degrees. Line a large baking sheet with parchment paper.

In a large bowl, cream butter and sugar until fluffy. Add peppermint extract and eggs, one at a time, until smooth and creamy.

In another large bowl, sift together flour, cocoa powder, baking soda and salt.

Gradually add flour mixture to wet ingredients until mixture forms a dough. Refrigerate for 30 minutes.

Scoop dough into balls, about one Tbsp. each. Roll balls in extra granulated sugar and place on prepared sheet, about two inches apart. Back for 8 minutes until slightly crackled. Pull tray out and sprinkle middle of each cookie with some crushed candy canes. Push tray back in the oven and continue cooking for 2 minutes. Transfer to wire rack to cool.

While cookies are cooling, place chocolate chips and shortening in a microwave safe bowl.

Microwave in 30 second intervals, stirring in between, until melted and smooth.

Dip half of each cookie into the chocolate and transfer to wax paper or parchment paper.

Sprinkle with additional crushed candy canes and let set.