Sift together (or gently stir with a whisk) the flour, cocoa powder, baking soda and salt. Set aside.
With an electric mixer cream together the butter, granulated sugar and brown sugar until fully incorporated and fluffy.
Beat in egg, coffee or liqueur, and vanilla.
3Add in flour/cocoa mixture about 1 cup at a time. Blend until fully incorporated. (If you are using a hand mixer you may need to add the last cup of flour by hand).
Divide dough into two or three large balls, place in a plastic bag and chill in the refrigerator 1-2 hours (if you’re in a hurry, you can chill the dough for about 20 minutes in the freezer).
Once chilled, work with one ball of dough at a time, and roll onto a lightly floured surface. I find it works best to place a sheet of parchment paper on top of the dough, and then roll on top of the parchment. This prevents the dough from sticking to your rolling pin, and you also don’t need to add as much extra flour (as you would without the parchment).
Cut out desired shapes with cookie cutters and place on a baking sheet.
Place the baking sheet (with cookies on it) in the freezer about 5 minutes (this helps the dough keep it’s shape when baked).
Bake cookies for 7-10 minutes (depending on size) in a 350*F oven.
Allow cookies to cool on baking sheet a few minutes and then transfer to a wire cooling rack.
Decorate as desired.