1. Make the Cookie Dough
I start by whisking together the flour, ginger, cinnamon, nutmeg, cloves, baking soda, and salt in a large bowl. Setting this aside, I grab another bowl and beat the softened butter and brown sugar with my electric mixer until it’s fluffy and lump-free about 2 minutes. Then, I add the egg, egg yolk, vanilla, and molasses, mixing until everything’s smooth and glossy.

Next, I gradually add the dry ingredients to the wet mixture on low speed. The dough will be thick and slightly sticky, but that’s normal! I scrape down the sides of the bowl, cover it with cling wrap, and let it chill in the fridge for at least 30 minutes (or up to 24 hours). Chilling is key here it prevents the cookies from spreading too much.

2. Bake the Cookies
Once the dough is chilled, I preheat the oven to 350°F and line two baking sheets with parchment paper. If the dough has been in the fridge longer than 2 hours, I let it sit at room temperature for 20 minutes to soften slightly. Using a cookie scoop (about 1.5 tablespoons per ball), I roll the dough into balls, then coat each one in turbinado sugar. The sugar adds a lovely crunch!

I place the dough balls 2 inches apart on the sheets they’ll spread a bit and bake for 8–10 minutes. The tops should look just set, but the centers will stay soft. Let them cool on the tray for 5–10 minutes before transferring to a wire rack. Patience is tough here, but it keeps them from breaking!

3. Whip Up the Eggnog Buttercream
While the cookies cool, I make the frosting. In a medium bowl, I beat the softened butter until it’s super smooth. Then, I add the icing sugar ½ cup at a time, mixing well after each addition. Once 2 cups are in, I drizzle in the eggnog 1 tablespoon at a time, plus the rum extract if using. The frosting should be thick but spreadable add more sugar if it’s too runny or a splash more eggnog if it’s stiff.

4. Assemble the Sandwiches
Here’s the fun part! I flip a cookie upside down, spread about 1 tablespoon of frosting on the flat side, and press another cookie on top. Gentle pressure helps the frosting squish to the edges. Repeat until all 16–18 sandwiches are done.