These cookie sandwiches are packed with holiday cheer, thanks to a hint of molasses and gingerbread spice in the soft, chewy cookies, as well as a generous dose of spiced cookie butter spread in the filling. Plus, there's an extra dusting of sanding sugar to add the perfect sweetness and festive sheen.
For the gingerbread cookies: Beat the butter, granulated sugar and brown sugar in a large bowl with an electric mixer on medium-high speed until light and fluffy, about 5 minutes. Beat in the molasses, vanilla and egg until smooth and combined, scraping down the sides of the bowl with a rubber spatula as needed. Meanwhile, whisk the flour, gingerbread spice, baking soda, baking powder and salt in a medium bowl. With the electric mixer on low, gradually add the dry mix into the wet until just combined.
Using a 3/4-ounce cookie scoop, scoop the dough onto a parchment-lined plate or baking sheet into uniform balls (you should have about 30 balls, each about 1 heaping tablespoon of dough). Sprinkle generously with sanding sugar. Refrigerate until chilled through, about 1 hour.
Preheat the oven to 350 degrees F and line 2 rimmed baking sheets with parchment.
Transfer the chilled dough balls to the prepared baking sheets, leaving about 2 inches between each. Bake until the tops are matte and the cookies puff slightly and are just set at the edges, 12 to 15 minutes. Let the cookies cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.
For the cookie butter filling: Beat the butter, cookie butter spread and salt in a large bowl with an electric mixer on medium-high speed until fluffy and thoroughly combined, about 5 minutes. Slowly add the confectioners' sugar 1/2 cup at a time, beating until combined and smooth. Transfer to a piping bag fitted with a large star tip.
Flip half the cookies over and evenly pipe on the cookie butter filling, then sandwich with the remaining cookies to make 15 cookie sandwiches. Refrigerate until the filling is just set, about 15 minutes. Serve immediately or refrigerate in an airtight container for up to 5 days.