Historically, whiskey sours often used egg white to create a foamy, silky texture without contributing additional flavor. Raw egg in a cocktail might seem a bit icky, but it’s no different than a meringue, say, or a Caesar salad dressing.
The trick to this is to use a “double shake” to make sure the egg white is fully incorporated: First shake without ice, to break up and aerate the egg white. Then, you shake a second time with ice, to cool everything down and make it extra frothy. For a variation, try using a mix of a few types of citrus, (I like ½ oz lemon juice plus and ¼ oz orange juice for a fruitier, sweeter flavor). —Carey Jones
Combine ingredients in cocktail shaker without ice. Shake hard, then add ice and shake again, until well-chilled. Strain into a rocks glass with fresh ice. Garnish with a few drops of bitters, dashed onto the pale foam head.
*To make the simple syrup: Dissolve 1 part sugar in 1 part hot water. Let cool before using.