Peppermint Mocha Kahlua Ganache

1. Place chocolate in a large, heat-safe bowl.
2. Microwave cream for about 1 minute, until just beginning to boil. Pour over chocolate, making sure to submerge completely. Let sit for 5 minutes, and then stir until smooth. If needed, microwave briefly (10 seconds or so) to ensure all chocolate is melted and ganache is smooth. Stir in Kahlua until smoothly incorporated.
3. Cover ganache and refrigerate until thick, stirring occasionally.

Chocolate Roll-Out Cookies

1. In a bowl, whisk together the flour, cocoa, espresso powder, baking powder, and salt.
2. In the bowl of a stand mixer fitted with the paddle attachment (or using a bowl and handheld electric mixer), cream together the butter and sugars until pale and fluffy. Wipe down the bowl and beater and add the egg, milk, and vanilla extract. Beat in until well-incorporated.
3. Wipe down bowl/beater and sift the dry ingredients into the wet. Mix in on lowest speed until all ingredients are almost evenly combined, and then finish folding in with a spatula, at which point the dough should be starting to clump. Use your hands to clump all of the dough together.
4. Divide dough in half and shape each half into a small, flat square on a piece of plastic wrap. Wrap and refrigerate for 1 1/2 - 2 hours, until cold and firm. Meanwhile, line two baking sheets with parchment paper.
5. Dust a surface for rolling with cocoa powder. Remove one portion of dough from fridge and dust top with cocoa. Roll out to 1/4" thick and cut out individual cookies with a linzer cookie cutter**, being sure to make an equal number of top and bottom cookies. Transfer cut cookies to prepared baking sheets, spread slightly apart, keeping tops and bottoms on separate baking sheets .
6. Ball up scraps, wrap in plastic wrap, and place in freezer. Repeat above process with second half of dough.
7. Briefly knead scraps with scraps from freezer and continue to roll, cut, bring together scraps, and repeat until all cookies are made.
8. Preheat oven to 325ºF. Freeze cookie sheets while oven is preheating, at least 10 minutes.***
9. Bake cookies in preheated oven for 8-10 minutes (top cookies) and 10-11 minutes (bottom cookies), flipping and rotating sheets halfway through, until cookies no longer look wet on top. (If you're unsure, I would still suggest not going over the maximum baking time written). Cool for about 10 minutes, and then transfer to a wire rack to cool completely before sandwiching and decorating.(At this point, the cookies can also be stored in an airtight container to finish later, if desired).

For Decorating:

1. Line a baking sheet with parchment paper.
2. Place white chocolate in a (preferably tall and narrow) microwave-safe container and microwave at 50% power for 1 minute. Stir and continue to microwave for 15-30 second increments at full power, stirring in between, until about 3/4 of the chocolate has melted. Continue to stir until smooth. Let cool to 96º-98ºF before dipping cookies.
3. One by one, dip top cookies halfway in chocolate and tap off excess. Transfer to parchment to set.
4. Once all cookies have been dipped and set, spread ganache onto bottom cookies with an icing spatula. (Or, for a neater presentation, pipe ganache around edges of cookies and in middle, and then use an icing spatula to spread out the middle without disturbing the edges.) Sandwich cookies and fill centers with sprinkles.
5. Store cookies in an airtight container in the refrigerator.