Vinegar doesn't jump to mind as a cocktail mixer, but when the tangy, bracing tonic is macerated with fresh fruit and sugar, it becomes a bartender's favorite: a shrub.
A well-made cocktail just wouldn't be complete without a bit of sugar (not to mention, it's great in iced tea and other chilled drinks, too). Sweetnes...
Bitters are making a comeback -- just walk into any bar or lounge today and you'll see more than just the requisite bottle of Angostura bitters behind...