1cup (2 sticks)unsalted butter,at room temperature
6ouncesbittersweet or semi-sweet chocolate,finely chopped
1/2cupfinely chopped red and white peppermint candies(you can use candy canes)
MAKE THE COOKIES:
Sift the flour, cocoa, and salt into a medium bowl. In a large bowl, use an electric mixer to combine the butter and sugar until smooth. Beat in the vanilla. Add the dry ingredients; beat until the dough holds together. Divide the dough in half. Shape each piece into a disk. Wrap in plastic wrap; chill until firm enough to roll, at least 45 minutes and up to 1 day.
Set a rack in the center of the oven and preheat to 300°F. Line 2 rimmed baking sheets with parchment paper. Roll out 1 dough disk on a floured surface to 1/4-inch thickness. Using 3-inch star-shaped cutter, cut out the cookies. Transfer to sheets, spacing 1-inch apart. Gather scraps into ball. Wrap; chill until firm, about 30 minutes.
Bake the cookies, 1 sheet at a time, until the tops feel firm to touch, about 25 minutes. Cool on the sheets for 10 minutes. Transfer the cookies to racks and cool completely. Repeat rolling, cutting, and baking until all of the dough is used.
PREPARE THE TOPPING:
Put a saucepan with a little bit of water in it over medium heat. Place the chocolate in a metal bowl and set it over the saucepan of barely simmering water; stir until smooth. (Alternately, you can melt the chocolate in a glass bowl in the microwave). Using a small spoon, drizzle the chocolate over the cookies in zigzag lines. Sprinkle with the crushed candies. Drizzle any remaining chocolate over. Let stand until the chocolate is set, at least 1 hour.
*The cookies can be prepared ahead. Store in an airtight container at room temperature up to 3 days or freeze up to 2 weeks. Add the topping when ready to serve. Chocolate and peppermint-topped cookies can be made 3 days ahead. Store the cookies between sheets of waxed paper in an airtight container at room temperature.