Boston Sour

Pro tips

• Dry shake the egg white first for 10-15 seconds without ice to build aeration, then add ice and shake again for proper dilution and a thick, stable foam.
• Chill your glass before serving to keep the drink cold longer and showcase the foam.
• Use fresh lemon juice, not bottled, for brightness and balance against the whiskey and sugar.
• Fine-strain into the glass to catch ice chips and egg white debris for a silky, clean texture.

Substitutions

• Old Mr. Boston Rye/Bourbon → Any mid-range rye or bourbon (1.5–2 oz works too depending on preference)
• Powdered Sugar → Simple syrup (1/2 oz) or 1/2 tsp superfine sugar mixed with a few drops of water
• Egg White → 1/2 oz aquafaba or 1/4 oz cream for a dairy-based foam (less stable than egg white)

Storage & make-ahead

Serve immediately after shaking. This cocktail does not store or keep.

Equipment

cocktail shaker · jigger · fine strainer · bar spoon

Do I need to use raw egg white in a Boston Sour?

Yes, raw egg white creates the signature silky foam. Use pasteurized eggs if concerned about food safety, or substitute 1/2 oz aquafaba (chickpea liquid) for a vegan alternative.

Can I make a Boston Sour without egg white?

Yes, omit the egg white for a simpler whiskey sour, but you'll lose the creamy foam texture that makes this drink distinctive.

What's the difference between rye and bourbon in this cocktail?

Rye whiskey adds spice and dryness; bourbon brings sweetness and smoothness. Choose based on your flavor preference.

How do I get a good foam on top?

Dry shake (shake without ice) first to aerate the egg white for 10-15 seconds, then add ice and shake again for proper dilution and a stable foam.

Can I batch a Boston Sour ahead of time?

Mix the whiskey, lemon juice, and powdered sugar up to 1 day ahead, but add egg white and shake with ice immediately before serving.