Chocolate Candy Cane Cookies (Chocolate Peppermint Sandwiches)

I brought these cookies to a cookie swap. It just so happened that THREE other people brought chocolate peppermint cookies as well. These were delicious even amongst the other chocolate peppermint cookies.
I used Dutch-processed cocoa so my cookies were dark in color and really had a deep chocolate flavor. The peppermint buttercream was so good, I had to stop myself from eating it with a spoon. I rolled my cookies in candy cane pieces, but if I was going to make these again I don't think I would go to the hassle. The candy cane pieces looked pretty, but were kind of a pain (they wouldn't stick on the frosting very well) and didn't add anything to the overall taste of the cookie.  Also, I added a lot more powdered sugar to my filling. I felt that the filling as written was a little greasy, so I added a cup or so more of powdered sugar. It ended up being a creamy dreamy peppermint filling. Yummy.

adapted slightly from Bon Appétit 

Yield: Makes about 18 sandwich cookie Ingredients  Cookies 1 3/4 cups all purpose flour 1/2 cup unsweetened cocoa powder (preferably Dutch-process) 1/4 teaspoon salt 1 cup sugar 3/4 cup (1 1/2 sticks) unsalted butter, room temperature 1 large egg Filling 1 cup plus 2 tablespoons powdered sugar (I used 2+ cups) 3/4 cup (1 1/2 sticks) unsalted butter, room temperature 3/4 teaspoon peppermint extract 2 drops (or more) red food coloring 1/2 cup crushed red-and-white-striped candy canes or hard peppermint candies (about 4 ounces) For cookies: Whisk flour, cocoa, and salt in medium bowl to blend. Using electric mixer, beat sugar and butter in large bowl until well blended. Beat in egg. Add dry ingredients; beat until blended. Refrigerate dough 1 hour. Preheat oven to 350°F. Line 2 baking sheets with parchment paper. Scoop out dough by level tablespoonfuls, then roll into smooth balls. Place balls on prepared baking sheets, spacing about 2 inches apart. Using bottom of glass or hands, flatten each ball to 2-inch round (edges will crack). Bake until cookies no longer look wet and small indentation appears when tops of cookies are lightly touched with fingers, about 11 minutes (do not overbake or cookies will become too crisp). Cool on sheet 5 minutes. Transfer chocolate cookies to racks and cool completely. For filling: Using electric mixer, beat powdered sugar and butter in medium bowl until well blended. Add peppermint extract and 2 drops food coloring. Beat until light pink and well blended, adding more food coloring by dropfuls if darker pink color is desired. Spread 2 generous teaspoons filling evenly over flat side of 1 cookie to edges; top with another cookie, flat side down, pressing gently to adhere. Repeat with remaining cookies and peppermint filling. Place crushed candy canes on plate. Roll edges of cookie sandwiches in crushed candies (candies will adhere to filling). (Cookie sandwiches can be made ahead. Store in single layer in airtight container at room temperature up to 3 days or freeze up to 2 weeks.)