For this cocktail from author and former Gramercy Tavern managing partner Nick Mautone, look for white crème de cacao (clear white-chocolate liqueur) in better liquor stores. DeKuyper makes a good one.
This recipe was featured in our 2006 Killer Apps menu.
Variation: Drop a white-chocolate kiss into the drink and sprinkle orange zest on top.
Every kitchen has some rules. Mine doesn't have too many but I admit to being a stickler for a few...