Get the Recipe
Many cocktail ingredients got their start as medicines. Gin, tonic, and lime helped to battle malaria and scurvy long before we started drinking the combination recreationally, and whiskey was both anesthesia and antibiotic. In what we can grudgingly call progress, modern doctors just aren't likely to prescribe an Old Fashioned or a shot of Fernet. (Though I swear that bourbon will kill a cold faster than OJ and bed rest.)
Amaro is yet another item from behind the bar that started out as a way to cure what ailed us—it was once a treatment for everything from an upset stomach or colicky baby to cholera. Really, "amaro" (or amari, in the plural) is just a general name for a bitter, herbal liqueur. The Italians, who know a lot about what and when to eat and drink, traditionally serve an amaro after a meal to aid digestion. Looking for French amari? Look for the word Amer on the bottle.
What's Available to Buy
Amari have been popular with bartenders for some time, and they're now in demand by more people on the other side of the bar. There are a bunch of different types and brands to choose from. The most ubiquitous (and least beloved) is Jägermeister. But some more, ahem, refined options that aren't too hard to find include Averna, Ramazzotti, Amer Picon, Cynar, Torani Amer, and Fernet Branca. They vary in flavor and bitterness—Averna, for instance, is on the milder side, while Fernet Branca will smack you upside the head.
If you're looking to make an exact copy of a particular brand of amaro, I'm going to stop you right there because trying to duplicate a proprietary mix of dozens (even hundreds) of ingredients could just frustrate you. And no one should be sad or mad when making an amaro, because it's actually really easy and fun to do.
But decide what flavors and characteristics you want, and you can create your own, unique bitter liqueur. It's up to you how bitter, vegetal, citrus-y, or nutty your homemade amaro will be. So, should you DIY or buy? The answer is both!
Just like any bitters recipe, you'll need three types of ingredients: at least one bittering agent (usually an herb or bark), flavoring ingredients (herbs, citrus, and vegetables, for example), and the base (a high-proof, neutral spirit, in this case, though some can be made with wine as well). I adapted a recipe from Luscious Liqueurs for an herbaceous and clean amaro that is on par with Averna when it comes to the level of bitterness.
Get the Recipe
Your amaro is made for sipping straight-up or on the rocks after a meal. But it can also add an interesting twist to cocktails like the Manhattan, such as in this High Time Manhattan.
The bitterness is also a nice counterpoint to sweet and tart flavors in a drink like the Cranberry Crush.
Another surprisingly good companion for bitter liqueur is dark cocoa, which you can play with in cocktails like Bitter Pumpkin #2.
You'll need to do a bit of taste testing and tweaking to suit your special amaro recipe, but it'll quickly become obvious that DIY amaro likes to be mixed as much as it likes to be sipped in a leisurely manner after a big meal.