- Yield: 24 sandwich cookies
For the Cookies
- 2¾ cups unbleached all-purpose flour
- 1¼ cups Dutch-processed cocoa powder
- ½ teaspoon fine sea salt
- ½ pound (2 sticks) unsalted butter, at room temperature
- 1 tablespoon pure vanilla extract
- 2 cups confectioners’ sugar
- ½ cup packed dark brown sugar
- 2 large eggs
For the Cream Filling
- 8 tablespoons (1 stick) unsalted butter, at room temperature
- 1 teaspoon peppermint extract
- One 1-pound box (4 cups) confectioners’ sugar
- A drop or two of green food coloring (optional)
For the Chocolate Coating
- 1¾ cups semisweet chocolate chips
- 8 tablespoons (1 stick) unsalted butter
How to Make It
- Line two cookie sheets with parchment. To make the Cookies
- Sift together the flour, cocoa powder, and salt; set aside.
- In the bowl of a stand mixer fitted with the paddle attachment (or in a large mixing bowl, using a handheld mixer), cream the butter, vanilla, and both sugars on medium speed until light and fluffy, about 3 minutes. Turn the speed down to low and add the eggs one at a time, beating until combined. Add the flour mixture in thirds, beating until just combined; scrape down the bottom and sides of the bowl as necessary.
- Transfer the dough to another bowl and finish mixing by hand to make sure no bits of flour or butter are hiding on the bottom of the bowl and the dough is mixed thoroughly.
- Divide the dough in half and place one half on each prepared cookie sheet. Place a piece of plastic wrap or another sheet of parchment on top of each one and use a rolling pin to roll out the dough to about ¼ inch thick. Wrap the baking sheets in plastic wrap and chill in the refrigerator for at least 30 minutes.
- Position a rack in the lower third of the oven and preheat the oven to 350°F.
- Remove one sheet of dough at a time from the refrigerator and transfer the cookie dough and parchment to the kitchen counter. Cut out cookies with a 2-to 3-inch round cookie cutter. Line the cookie sheet with fresh parchment and place the cutout cookies on the pan, leaving about 1 inch between the cookies to allow for spreading. Chill the cookies in the refrigerator for at least 15 minutes, while you cut out the second pan of cookies. Use the scraps of dough one time to cut out more cookies.
- Bake the cookies, one sheet at a time, for 8 to 10 minutes. The cookies are done when they are firm to the touch and the smell of chocolate has begun to fill the kitchen. Transfer the cookies to a wire rack to cool completely. To make the Cream Filling
- In the bowl of a stand mixer fitted with the paddle attachment (or in a large mixing bowl, using a handheld mixer), cream the butter and peppermint extract together until smooth. Gradually add the confectioners’ sugar, mixing until light and fluffy. If desired, add a drop or two of green food coloring, mixing until the filling looks minty. To Sandwich the Cookies
- Put a dollop of filling (about 1 tablespoon) on the bottom of one cookie and place another cookie right side up on top. Repeat with the remaining cookies. To coat the Cookies
- Set a heatproof bowl over a saucepan of simmering water (make sure the bottom of the bowl does not touch the water), add the chocolate chips and butter, and stir frequently until they have completely melted. Remove the bowl from the heat.
- Set a wire rack on a cookie sheet lined with wax paper or parchment to catch the chocolate drippings. Using two forks, quickly dip each cookie into the warm chocolate, turning to coat, then gently place the cookie on the wire rack. If the dipping chocolate begins to harden, return it to the simmering water and stir until it melts again. Let the cookies stand until set. Store the cookies in an airtight container for up to 3 days at room temperature.