For the Cookies
- 2 ¼ cups all-purpose flour
- 1 Tbsp. finely ground coffee or espresso
- 1 ¾ tsp. baking soda
- 1 ½ tsp. ground cinnamon
- ½ tsp. ground ginger
- ½ tsp. kosher salt
- ¼ tsp. ground allspice
- ¾ cup (1 ½ sticks) unsalted butter, melted, cooled
- ½ cup (packed) dark brown sugar
- ¼ cup mild-flavored (light) molasses
- ¾ cup granulated sugar, plus more for rolling
- 1 large egg
For the Filling and Assembly
- 3 Tbsp. unsalted butter, cut into pieces
- 8 oz. blond chocolate, such as Dulcey, or milk chocolate, divided
Make the Cookies
- Whisk flour, coffee, baking soda, cinnamon, ginger, salt, and allspice in a medium bowl.
- Whisk butter, brown sugar, molasses, and ¾ cup granulated sugar in a large bowl until smooth (it may stiffen and separate at first; keep whisking until it loosens up). Whisk in egg.
- Add dry ingredients to butter mixture. Mix with a silicone spatula or wooden spoon just until combined. Cover and chill dough until firm, at least 20 minutes or up to overnight.
- Place a rack in middle of oven; preheat to 375°F. Place granulated sugar in a shallow bowl. Working with about one-quarter of dough and chilling remaining dough while you assemble and bake, scoop dough by the tablespoonful and roll into balls; you should get 10 per batch. It’s important to bake only 1 sheet of cookies at a time; they’re very temperature-sensitive and will spread too much otherwise. Roll balls in granulated sugar, then arrange on a parchment-lined baking sheet, spacing 2″ apart.
- Bake cookies until centers are cracked and edges are set, 5–7 minutes. Resist the urge to bake the cookies longer; the aim is to maintain their chew and they will continue to crisp as they cool. If cookies are puffed, tap pan against counter as soon as they come out of the oven to deflate. Transfer pan to a wire rack and let cool 5 minutes. Remove cookies from pan and let cool completely. Repeat with remaining dough for a total of 4 batches and 40 cookies.
Dough can be made 1 day ahead. Keep chilled. Unfilled cookies can be made 5 days ahead. Store in an airtight container at room temperature.
Make the Filling and Assemble
- Place butter and 6 oz. chocolate in a large bowl. Bring cream just to a boil in a small saucepan over medium-high heat. Remove from heat, then stir in coffee, vanilla, and salt. Pour hot cream mixture over chocolate and butter and whisk until smooth. Chill until ganache is cooled and thickened, about 20 minutes. Beat with an electric mixer or vigorously by hand with a whisk until lightened in color and stiff.
- Melt remaining 2 oz. chocolate in a small saucepan over medium-low heat. Transfer to a pastry bag and snip off end of bag (or use a resealable plastic bag and cut off 1 corner) to make a very small opening.
- Place 1 rounded tablespoon of filling on each of cookies. Pipe thin lines of melted chocolate over in desired design.
Filled cookies can be made 2 days ahead. Store in an airtight container at room temperature.