With its cozy seating and familiar bar staff, it appears that little has changed at The Passenger’s new Shaw location that opened last week. One look at the tap handles, however, and one distinction becomes apparent: they’re now serving both yellow and green Chartreuse on draft.

General manager Jade Aldrighette pours a shot of each from custom-made tap handles featuring the French liqueur’s medallion logo. The spirit is bright and translucent—no bubbles—with “a light chill on it as nitrogen gas doesn’t have a huge effect,” says Aldrighette. The nitrogen does smooth out the texture. Still regarded as a rare liqueur and sold in limited quantities, the low price of only $6 dollars an ounce ensures that all guests can taste the Chartreuse neat. Or they have have it mixed in a cocktail.

Aldrighette says they used to have Fernet on draft, but they chose to install a Chartreuse tap when they reopened because of its growing popularity, particularly in craft cocktails: “It’s so complex and flavorful and it’s very versatile.” She said that so far the tap has been “super popular.”

Every day, the bar will be whipping up a new cocktail with Chartreuse in it. A recent drink was the refreshing French Dandy, which pairs yellow Chartreuse with cognac, orange and lemon juice, ginger beer and angostura bitters.

The Chartreuse recipe dates back to a medieval manuscript from 1605, making it one of the world’s oldest liqueurs. It is still produced according to the original recipe by Carthusian monks of the Grand Chartreuse monastery in Voiron, France, and only two monks are allowed to know the whole recipe.

They have developed a special relationship with the brand’s rep, and she says their goal is to have the biggest Chartreuse account. The Passenger now has a Chartreuse cross logo on the wall and they serve the liqueurs from hand-painted canisters and taps from France. No one has ever installed both a green and yellow tap. Aldrighette says, “So we had to do it.”

Aldrighette says choosing one or the other is personal preference, and some even mix them or like adding bitters to their shot. But the deliciously sweet and herbal liqueurs are not for the faint of heart. The green is 110-proof and yellow is 80-proof.

“Their botanical recipes are different,” she says, referring to the secret blend of 130 alpine herbs, berries and fruits infused into the spirit that give it its strong vegetal flavor. “Green is more complex, with its higher proof it can hold more flavor. Honey is in the yellow, which is the overlooked little sibling of the big ‘green monster,'” Aldrighette explains.

Chartreuse shots are popular with guests and off duty bartenders from Ivy & Coney next door. And unlike much of The Passenger’s rotating cocktail menu, Aldrighette says Chartreuse will stay on tap for the foreseeable future.

The Passenger’s new location is at 1539 7th Street NW in Shaw

Editors’ note: A previous version of this story says that the monks gave their blessing for the tap and that The Passenger has the largest Chartreuse account in the country. In fact, the bar works with representatives for the liqueur not the monks themselves, and The Passenger does not have the largest account in the country.