Caper berries, the fruit of the caper plant, have been growing across the Mediterranean Basin for at least as long as olives have. These two small fruits have plenty in common, including the fact that both need to be cured or brined in order to soften the natural compounds that render them too bitter to consume untreated. This recipe uses caper brine as you would use olive brine for a dirty martini, giving the cocktail a Sicilian twist.