The Whiskey Sour is one of the oldest cocktail templates in existence — a formula so durable and sensible that it predates the word "cocktail" itself. Jerry Thomas included a version in his 1862 guide. The structure (spirit, citrus, sweetener) underpins dozens of modern classics. Master the Sour and you understand half of mixology.

The Ratio

2:1:¾ is the classic Whiskey Sour ratio — 60ml bourbon, 30ml lemon, 22ml syrup. It's close but not identical to a Daiquiri (which runs similarly), and the distinction matters: bourbon is sweeter and richer than rum or vodka, which means the citrus needs slightly more room. Some bartenders work at 2:1:1, which is softer. Try both and decide which suits your palate.

What you must not compromise on is the lemon. Fresh juice only. The difference between fresh and bottled citrus in a Sour is not subtle — it is the difference between a cocktail and a drink.

The Egg White Question

A classic New York Sour or Boston Sour includes egg white; many bars omit it for speed. The case for including it is strong: egg white adds a silky, dense foam that changes the mouthfeel completely, softening the sharp citrus hit and creating a richer, more satisfying texture.

The technique matters. Dry shake first — without ice — for 15 seconds to emulsify the egg white. Then add ice and shake hard for another 10–12 seconds to chill and dilute. Strain into a rocks glass over a large cube. The foam should sit above the surface in a clean, white cap.

If serving without egg white, shake once with ice and strain directly.

Bourbon Selection

The bourbon matters more than people expect. High-proof options (Wild Turkey 101, Maker's Mark Cask Strength) hold up against the lemon and provide a more assertive backbone. Lower-proof bourbons (Buffalo Trace at 90 proof) work fine but require less syrup to maintain balance. Avoid anything too delicate or floral — the citrus will overwhelm it.

Rye whiskey is an excellent substitute: drier, spicier, and particularly good if you prefer your Sour on the sharper end.

Variations Worth Knowing

• New York Sour — float a thin layer of dry red wine on top of the finished drink. The wine adds a tannin contrast and makes for an arresting presentation.
• Amaretto Sour — swap bourbon for amaretto, add a small amount of overproof bourbon for backbone (Jeffrey Morgenthaler's version is definitive). Far better than its reputation.
• Pisco Sour — replace bourbon with Peruvian pisco and add a few drops of Angostura bitters on top of the foam. A different drink entirely, but the same template.