Penicillin

Classic Cocktail

A modern classic Scotch sour built with blended Scotch, fresh lemon juice, honey-ginger syrup, and a smoky Scotch float.

Method

Method & Technique

The Penicillin is a shaken citrus cocktail finished with a smoky Scotch float.

Add blended Scotch, fresh lemon juice, and honey-ginger syrup to a shaker tin. Add ice and shake hard until the cocktail is fully chilled and properly diluted. Strain into a rocks glass over one large cube or fresh ice.
Add the smoky Scotch last, floating it carefully across the surface of the completed drink. Garnish with candied ginger.

Do not shake the peated Scotch into the base cocktail. The float is not simply an additional portion of whisky. Its position at the surface controls how the guest experiences the drink: smoke reaches the nose first, followed by lemon, honey, ginger, and the softer Scotch underneath.

The float must be measured. Too little may disappear, while too much can overpower the base drink and make the cocktail taste medicinal, ashy, or aggressively smoky.

The honey-ginger syrup also requires a controlled house recipe. It should provide clear honey flavor, fresh ginger heat, and enough sweetness to balance the lemon without becoming sticky or heavy. It must be prepared before service, strained thoroughly, tasted, refrigerated, labeled, and dated.

Fresh lemon juice is essential. It supplies the acidity that keeps the honey, ginger, and Scotch energetic and balanced.

The finished drink should be cold, bright, spicy, honeyed, Scotch-forward, and lightly smoky.

Related Core Methods

Guest Story

The Penicillin is an excellent recommendation for guests who enjoy Whiskey Sours, Scotch, ginger, honey, or cocktails with a controlled smoky finish.

A useful guest description is:
“It’s a modern Scotch sour made with fresh lemon, honey, and ginger, finished with a small float of smoky Scotch. It’s bright, spicy, lightly honeyed, and aromatic without being overwhelmingly smoky.”

It is a strong bridge for guests who are interested in Scotch but do not want a neat pour or an aggressively smoky drink. The lemon and honey make the cocktail familiar, while ginger adds energy and the peated float introduces smoke in a controlled way.

Do not describe it simply as a smoky cocktail. That can cause guests to expect a much heavier drink. The Penicillin is primarily a bright Scotch sour; smoke is the aromatic finish.

For the bartender, it teaches citrus balance, syrup control, vigorous shaking, fresh-ice service, and proper floating technique.

For the owner or operator, it offers strong perceived value. It uses recognizable flavors, introduces guests to Scotch in an approachable format, and presents like a premium cocktail without requiring an overly complicated service build.

Method

Guest Story

Origin

Where It Came From

The Penicillin was created in 2005 by Australian bartender Sam Ross at Milk & Honey in New York City.

Ross was building from the Gold Rush, another influential modern cocktail created at Milk & Honey. The Gold Rush combines whiskey, fresh lemon, and honey syrup. Ross reworked that structure with blended Scotch, added ginger to the honey-and-lemon combination, and finished the drink with a small amount of heavily peated Scotch.

That final float became the Penicillin’s defining move. Instead of making the entire cocktail intensely smoky, Ross concentrated the peated whisky at the surface, where its aroma reaches the guest before the first sip. Underneath it sits a bright, balanced Scotch sour built around lemon, honey, and ginger.

The drink became a favorite at Milk & Honey and spread rapidly through the modern cocktail community. Its clear construction, memorable flavor, and ability to make Scotch approachable helped it become one of the most influential cocktails created during the early twenty-first-century cocktail revival.

The name plays on the familiar, comforting combination of honey, lemon, and ginger, ingredients commonly associated with soothing hot drinks. It is a clever cocktail name, not a medical claim.

For service, the Penicillin should be cold, bright, gingery, honeyed, Scotch-forward, and lightly smoky. The float should complete the drink rather than dominate it.

Notes

Bartender Notes

Deep Dive

The Penicillin is one of the clearest examples of how a bartender can build a lasting modern classic by developing an existing cocktail structure rather than adding unnecessary complexity.

LMA Service Spec
2.00 oz Blended Scotch
0.75 oz Fresh Lemon Juice
0.75 oz Honey-Ginger Syrup
0.25 oz Peated Scotch Float
Candied Ginger

The drink is fundamentally a Scotch sour. Blended Scotch provides the base, lemon provides acid, honey-ginger syrup supplies sweetness and spice, and peated Scotch supplies the aromatic finish.

Why Blended Scotch Is the Base
Blended Scotch is the correct base because it provides enough malt, grain, oak, fruit, and whisky structure to remain present without overwhelming the lemon, honey, and ginger.

A heavily peated whisky used as the full two-ounce base usually changes the drink dramatically. The cocktail becomes smoke-led rather than balanced, and the lemon and honey may struggle to remain clear.

An extremely light blended Scotch presents the opposite problem. It may disappear behind the syrup, citrus, and float.

The house whisky should therefore be tested in the finished drink. The goal is not to find the smokiest base. The goal is to create a complete Scotch sour before the peated float is added.

The Peated Scotch Float
The float is one of the most intelligent parts of the recipe.

Aroma has an enormous effect on perceived flavor. By placing the peated whisky at the surface, the bartender creates the impression of a smokier drink without saturating the entire cocktail with peat.

When the guest raises the glass, the nose encounters smoke first. The sip then reveals lemon, honey, ginger, and blended Scotch underneath. That sequence is central to the experience.

A quarter ounce is enough for the standard build. An especially intense peated whisky may require a slightly smaller amount after testing. Increasing the float simply to make the drink more dramatic usually damages its balance.

The float may be applied over the back of a barspoon or poured gently across the top. A perfectly separated visual layer is less important than keeping the aromatic whisky concentrated near the surface.

Honey-Ginger Syrup
The syrup cannot be treated as an undefined mixture of sweet ingredients.

The original idea combined honey sweetness with fresh ginger character. In modern restaurant service, those elements are usually prepared as one standardized honey-ginger syrup so that every bartender can produce the same drink quickly.

There are several workable production methods. Fresh ginger juice can be combined with prepared honey syrup. Ginger may also be blended or steeped into the syrup and then strained. The exact method can vary, but the operational result must remain consistent.

The syrup should have:
Recognizable honey flavor
Fresh ginger aroma
Noticeable ginger heat
Pourable consistency
No coarse ginger fibers
Predictable sweetness

A weak syrup makes the drink taste like an ordinary Scotch sour. An excessively hot syrup makes it harsh. Too much honey makes the drink heavy and leaves the Scotch buried.

Straight honey should not be squeezed directly into the shaker. Cold honey can seize, stick to the tin, and incorporate unevenly. That creates inconsistent sweetness and unnecessary service delays.

Fresh Lemon
Fresh lemon is non-negotiable.
The cocktail carries honey, ginger, whisky, and smoke. Without clean acidity, those ingredients become dense and dull. Fresh lemon cuts through that weight and gives the cocktail its refreshing quality.
Old or bottled lemon juice causes the entire drink to taste flat, regardless of how expensive the whiskies are.

Shaking and Ice
Shake the base drink hard with quality ice.
Shaking chills, dilutes, aerates, and integrates the viscous syrup with the Scotch and lemon. A weak shake leaves the drink warm, heavy, and uneven.

The cocktail should be strained over fresh ice rather than served with the worn shaker ice. A large cube provides a polished appearance and slower continued dilution. Quality fresh cubes are also appropriate when that better suits the operation.

The float is always added after the base drink has been strained.

Garnish
Candied ginger is the clean LMA standard because it reinforces the ginger in the recipe and gives the guest a small edible element without cluttering the drink.
A lemon twist can work as an intentional house variation when more citrus aroma is desired. A lemon wheel is acceptable for a more casual presentation, but the drink should not be heavily garnished.

Variations
The Penicillin’s structure has inspired an extensive family of variations. Bartenders may change the base to bourbon, rye, Irish whiskey, rum, brandy, tequila, or mezcal. The cocktail may also be served hot, frozen, up, or lengthened.

Those are useful directions for signature-cocktail development, but they should not blur the identity of the classic training standard:
Blended Scotch
Fresh lemon
Honey and ginger
Peated Scotch float

A properly made Penicillin should be cold, bright, spicy, honeyed, balanced, and Scotch-forward with smoke concentrated at the nose and finish. It should not be syrupy, flat, overwhelmingly smoky, aggressively tart, or so ginger-heavy that the whisky disappears.