“It’s not god’s gift to classic cocktails,” admits Kevin Armstrong about the original recipe for his London bar’s eponymous cocktail, the Satan’s Whiskers. A mucky blend of two parts each of sweet and dry vermouths, gin and orange juice, with one part orange liqueur—served “straight” if it’s Grand Marnier, or “curled” with orange Curaçao—and a dash of orange bitters reads like a cocktail a young bartender might have whipped together at home with the only ingredients they had on hand. Alas, the Satan’s Whiskers, which was first published in Harry Craddock’s The Savoy Cocktail Book in 1930, still lingers in certain cocktail circles today.

To be able to serve the cocktail at its namesake bar in good conscience, Armstrong knew that the drink needed some significant changes. “It’s one of those drinks that can be fucked up in numerous ways,” he says, rattling off some of the possible mistakes: “wrong gin choice, bad juice, not enough body, overly potent vermouths and taking it too far in terms of water content.”

Like many historic drinks that prescribe large quantities of orange juice without the support of lemon or lime juice, it’s difficult to find the right balance between acidity and sweetness in the Satan’s Whiskers. But Armstrong insists that the orange juice alone shouldn’t be the cocktail’s scapegoat, as has often been the case with the orange juice–laden Blood & Sand. “Whatever you do, don’t blame the orange juice,” he says. In fact, he doesn’t shy away from it; instead, he adds a touch more than the classic Savoy recipe suggests. The key, he says, is fresh citrus. “If you’re going to use carton [juice], don’t even bother making the drink,” says Armstrong.

To give the orange note another dimension, Satan’s Whiskers employs a regal shake: An orange slice is tossed into the tin when shaking, adding extra aromatics from the peel’s oils. Then, to compensate for orange juice’s lack of acidic pop, Armstrong adds a dose of lemon juice to his take along with equal parts simple syrup, which complements the richness from the standard dose of Grand Marnier. 

For Armstrong, the main culprit making the typical Satan’s Whiskers washed-out and flabby is the amount of vermouth, which typically outweighs the gin. To give the drink a stronger alcoholic backbone, he chose a gin bottling with a higher ABV. “Classic London dry has always worked best for us, as some of the more floral, less juniper-forward gins don’t tend to hold up as well,” says Armstrong. He opts for Tanqueray and slightly ups the amount to 25 milliliters (a heavy three-quarter-ounce pour), while cutting the volumes of both dry and sweet vermouths in half to let gin be the star of the cocktail. And, instead of the typical sweet vermouth, this Satan’s Whiskers spec swaps in Punt e Mes for its orange top note and amaro-like bitterness.

The final consideration for Armstrong was the water content—the most overlooked component of any cocktail. “It’s very possible to overshake the drink,” he says. “If using our recipe, reduce the shake time a little, but still be snappy and aggressive.” The shorter shake means the drink doesn’t get as cold, so preparing frozen cocktail glasses ahead of time is essential.

After all of these upgrades, Armstrong is aware that, without completely reconceptualizing this classic, there’s no way of making it particularly exceptional. “Even with some decent tweaking, there’s no shame in saying there are plenty better drinks,” he says. But for him, that’s OK. Some drinks are simply relics meant to transport you back in time, or, in the case of the Satan’s Whiskers, inspire the name of one of the world’s best bars.