Cocktail lovers have gotten used to seeing margaritas, Manhattans and even Fernet Branca on tap at D.C. cocktail bars. But the tiny Red Apron Butchery's bar at Union Market is ahead of the game. On Friday, Red Apron will introduce a pre-mixed draft combination of the locally distilled Green Hat gin with a house-made sage and green apple tonic. And as early as next month, the bar may start pouring its own amaro, the bitter Italian liqueur that is currently riding a wave of popularity.

Git Tap A tap at Union Market's Red Apron Butchery will begin dispensing pre-mixed gin and tonics on Friday, April 5, 2013. The gin used is the D.C.-based Green Hat. (Photo by Fritz Hahn/The Washington Post)

The Green Hat and Tonic was crafted by J.P. Fetherston, currently of Union Market's Rappahannock Oyster Bar and formerly of the Columbia Room, in consultation with Columbia Room owner Derek Brown. The recipe took "three to four months" to hash out, Fetherston says, and uses agave nectar, thyme and citrus as well as sage and green apples. In a nod to Washington's first post-Prohibition distillery, the tonic was specifically designed for the herbal base of Green Hat. "I guess it would work with Plymouth [gin]," Fetherston concedes, "But it wouldn't match up nearly as well" as it does with Green Hat.

Both gin and tonic flow quickly out of a single tap handle, creating a frothy, easy-drinking mix that blends elements of cream soda, gin botanicals and plenty of apple. (By design, it's not as acidic or gassy as commercial tonics.) The characteristic juniper and cardamom take a backseat to cinnamon and citrus in the nose. Due to the ratio of gin to tonic, an average glass is around 11 percent alcohol by volume, Brown says, or slightly stronger than a heavyweight Belgian beer.

Look closely at Red Apron's bar and you'll see three other taps next to the gin and tonic handle: Two will dispense wine, says Brent Kroll, wine director for Neighborhood Restaurant Group. The last tap will lie vacant until next month, Fetherston says, when he hopes to unveil a locally distilled amaro, developed to the taste of Red Apron butcher Nathan Anda. The amaro will be produced by New Columbia distillers, the creators of Green Hat, and like the gin and tonic, it will be served carbonated from the tap. "It's going to be funky and awesome," Fetherston says, comparing his in-progress versions to "Campari and tonic or an Americano." We can't wait. In the meantime: Anyone for a gin and tonic?