How to Make the Penicillin Cocktail, According to Its Inventor

Here's the firsthand story behind the most healing whisky cocktail ever created—and how to make it like its inventor, Sam Ross.

Of all the drinks to enter the cocktail lexicon over the most recent cocktail renaissance (nominally, from 2004 to 2019), penicillin may be the most enduring. The four-ingredient drink can be found on cocktail menus from New York to Paris to Sydney and beyond. 

Here's a short lesson on the history of the iconic drink and how to make your own penicillin at home—straight from the bartender who created it, Sam Ross.

Related: How to Make the Penicillin Cocktail, According to Its Inventor

What Is in a Penicillin Cocktail?

The penicillin is a combination of Scotch whisky, ginger, honey, and lemon,

Its name speaks to the medicinal-ish qualities of the ingredients found within—as well as the quasi-curative history of cocktails. Whether or not penicillin discoverer Alexander Fleming would be tickled remains a question, but we like to think he would. He was a Scot, after all. The drink traces its origins back to some of the most hallowed ground in the modern cocktail world, Milk & Honey. In 2004, Sam Ross moved from Melbourne, Australia, to New York to work for Sasha Petraske at the iconic bar. It was there that Ross put together the ingredients that became the famed cocktail.

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After running Milk & Honey for eight years with Michael McIlroy, Ross and McIIroy were able to take over the space in 2013 when Sasha moved Milk & Honey to a bigger location on 23rd Street. It’s there that they opened Attaboy in March 2013. Since then, Attaboy has gone on to be named the Best Bar in North America (2022).

Despite its popularity, it's hard to find a good penicillin. So when I heard Ross was bartending for less than an hour at possibly the most famous of downtown Los Angeles’ speakeasies, The Varnish, there really wasn’t much of a choice. 

Down the steps, through the wooden door, past the French dip smell, and through the hidden portal in the back wall I went. There was Ross—among a cluster of other spirits writers, all of us eager to get our hands on the real thing.

“John Glaser of Compass Box [founder and head whisky maker] had dropped us off a batch of his newest whisky releases in 2005 and I started to play around with a riff on a Gold Rush [bourbon, lemon, and honey]," says Ross, explaining how it all began. "I used the Asyla, a lovely and mild blend, as the base of the drink and I split the sweetening component up between honey and our fiery fresh ginger syrup. 

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The drink came out well—balanced and nuanced, Ross recalls, but he wasn’t quite done with it yet. 

"I grabbed the bottle of super-smoky Peat Monster and floated a bar spoon on top of the giant rock of ice keeping the drink cold," he adds. "And that’s how the penicillin was born.”

How to Make a Penicillin Cocktail

Ingredients

● 2 ounces blended Scotch

● 0.75 ounces fresh lemon juice

● 0.75 ounces honey/ginger syrup*

Instructions

1. Shake all ingredients with ice and strain over a giant ice rock in a chilled rocks glass. 
2. Float the bar spoon of Islay on top and garnish with candied ginger. No straw!

“Fresh is always best, so juice your citrus to order," Ross emphasizes. "If you don’t have a Breville juicer for the ginger, muddle a big hunk of ginger in your shaker before you add the other ingredients—and bump the honey component up to 0.75 ounces to balance out the acidity from the lemon.”

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As for what whisky to use, Ross these days points to Benriach. “The drink works wonderfully when you shake with The Original Ten and float The Smoky Twelve on top.” 

Elsewhere, Monkey Shoulder is “a great example of a blend that works well—and any smoky Islay [whisky] for the float, depending on how potent you like it."

Ross’ honey syrup* is three parts honey to one part hot water. The ginger syrup, meanwhile, is four parts fresh ginger juice to three parts granulated sugar (by weight), stirred until the sugar is fully incorporated. He suggests keeping the ginger syrup refrigerated so it lasts for three to four days.