If you already know you're a Fernet person, this is the bottle to keep on your bar. If you don't know yet, it's the amaro San Francisco adopted as its own. Fernet-Branca started out in 1845 as a medicinal preparation that Bernardino Branca, an apothecary, made in his laboratory in Milan. The formula of 27 herbs, roots and spices is still a secret, and the company is still family-run, with the sixth generation now in the business. The botanicals come from around the world: rhubarb from China, gentian from France, galanga from India or Sri Lanka and chamomile from Europe or Argentina. They're infused, extracted or decocted, then the blend rests for a full year in oak barrels. It tastes like nothing else on the back bar, which is exactly why its fans get so evangelical about it. Sip it neat or on the rocks after a big dinner, or mix it with cola, the signature drink in Argentina. Ginger ale or chinotto work too, and it's the backbone of a classic Hanky Panky.