Directions

1. Place bittersweet chocolate and butter in a microwave-safe bowl. Heat in microwave at half-power in 30-second increments until the butter has melted and the chocolate melts when stirred. Stir until smooth. Set aside to cool for at least 10 minutes.
   
2. In a medium bowl add flour, baking powder, and salt then whisk togeter and set aside.
   
3. Place the brown sugar, Kahlua, eggs, and vanilla in a large mixing bowl. Use an electric mixer on medium speed to mix well. Add the cooled chocolate mixture, and mix until incorporated.
   
4. Reduce mixer speed to low. Gradually add the flour mixture, mixing just until combined. Fold in the chocolate chips by hand. Chill the dough in the refrigerator for 1 hour or overnight.
   
5. Preheat oven to 350°F. Line baking sheets with parchment paper or silicone liners. Drop dough by tablespoonfuls onto prepared pans. Flatten the top of each cookie slightly. Bake 12 to 15 minutes. The cookies should still be slightly soft in the center. Cool the cookies on the pans for 5 minutes. Then transfer the cookies to a wire rack to cool completely.