Yanni Kehagiaras of San Francisco’s Stoa Bar tends to eschew garnish in his drinks, preferring to let their innate beauty speak for them. Bitter End is no exception, with its magnificent float of aromatic bitters creating a stunning gradient through the glass. Drinking it is an equally lovely experience, as the spice of the bitters becomes potent on approach, and then gives way to a bracing, unsweet rum sour.