The Boston Sour is a classic whiskey cocktail combining rye or bourbon with fresh lemon juice, powdered sugar, and egg white to create a silky, foamy drink. The egg white distinguishes it from a standard whiskey sour, adding velvety texture and visual appeal.
Recipe Source
Visit Mr. Boston DrinksFrom Mr. Boston Drinks · by Old Mr. Boston De Luxe Official Bartender's Guide
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Shake well with cracked ice and strain into 8 oz.
highball glass.
Then add piece of ice, fill with carbonated water and decorate with half-slice of lemon and a cherry.
Serve immediately after shaking. This cocktail does not store or keep.
cocktail shaker · jigger · fine strainer · bar spoon
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.
Yes, omit the egg white for a simpler whiskey sour, but you'll lose the creamy foam texture that makes this drink distinctive.
Rye whiskey adds spice and dryness; bourbon brings sweetness and smoothness. Choose based on your flavor preference.
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.
Mix the whiskey, lemon juice, and powdered sugar up to 1 day ahead, but add egg white and shake with ice immediately before serving.
