Depending on your coffee liqueur, this can be a tad on the dry side so I've added a splash of sugar. Hence, according to your own tastes, you may want...
I used Mr. Black coffee liqueur, which is a bit drier than Kahlua, but for sweetness I used just a little maple syrup. I also added 1/4 oz. of triple sec to round out the flavor and play off the orange bitters.