The Black Forest is a recipe from the long-out-of-print Angostura Professional Mixing Guide. It’s a lovely old coffee cocktail that deserves a renaissance! The flavor is coffee-forward, but does indeed taste a bit like Black Forest cake.
The original recipe calls for orange bitters, which add a lovely floral note. If you don’t have any, or want to punch up the cherry notes, you can use cherry bitters instead. The sweet herbal liqueur specified is Bénédictine, made from honey and herbs.
For an extra punch of caffeine, try chilled espresso in place of the typical coffee.
Shake all ingredients with ice and strain into a flute glass.