Sloe gin, the liqueur that is the base for the lovely Hermione Granger, is a bit of a mystery to even my most booze-educated friends. "Um...what's that?", I always get asked, when I tell them that delicious tartness comes from sloe gin. Like a lot of forgotten cocktail ingredients resuscitated in recent years, sloe gin has a pretty interesting history. Read all about it at the Kitchn, where I'll be guest-writing a cocktail column for the next three weeks.