Whiskey Sour

Egg white does a few things brilliantly in a "sour" cocktail...
The protein subdues flavours, meaning it calms the sharp bite from acidic citrus. The pleasing layer of froth makes a nice canvas for garnishes, but more than that the thick, velvety foam makes the cocktail much smoother than without.
The orange or pineapple juice in the recipe is entirely optional but I find it further adds a bit of weight and rounder mouthfeel, especially if using a whiskey that tastes fantastic but feels a tad thin on the tongue.
Ingredients
60 ml Straight rye whiskey
30 ml Fresh lemon juice
15 ml Orange or pineapple juice
5-10 ml Rich syrup (2:1) or flavoured syrup
2 dashes Peach bitters
1 Pasteurised egg white
Garnish
Dried fruit slices, edible flowers, bitters, or citrus twist
Tools
Jigger, bar spoon, cocktail shaker, mesh strainer
Serve in a Coupe glass.
❶ Chill the coupe glass and prepare garnish.
❷ In a shaker add all ingredients, except ice.
❸ Without ice, shake with anger for 25-30 seconds.
This 'Dry Shake' method breaks up, whips up and emulsify the egg white.
❹ Add ice and shake with passion for about 12 seconds.
❺ Double strain into the chilled glass.
❻ Allow a few moments for the layers to settle.
❼ Garnish and serve.