Flavors, like fashion trends, ebb and flow as tastes change—but chocolate will forever have a slot on the VIP list. And while chocolate liqueur may conjure notions of decadent drinks that are more milkshake than cocktail, this homemade crème de cacao from New York restaurateur Eamon Rockey captures the toasty, nutty flavors and delightful bitterness of dark chocolate. Rockey keeps a batch on hand for classic cocktails, and particularly enjoys it in the 19th Century cocktail (a riff on the 20th Century) devised by Brian Miller during his time at Pegu Club.