Bitters are highly concentrated tinctures of botanicals, barks, herbs, and spices used in tiny doses to season and elevate cocktails much like salt does in cooking. They serve as the backbone of countless classic recipes — from the Old Fashioned to the Manhattan — providing aromatic complexity and tying together disparate flavor elements. Despite being used in dashes, their impact is profound, adding bitterness, depth, and a finishing aromatic quality that transforms a drink.