A crisp, lemon-bright gin sour — essentially a Sidecar that swaps brandy for gin — built from gin, triple sec, and fresh lemon juice shaken hard and served up. Its origin is contested: Harry MacElhone is credited with an early version at Ciro's Club in London around 1919, later reworking it into its gin form at Harry's New York Bar in Paris, while the American Bar at the Savoy claims Harry Craddock created it, codifying the build in his 1930 Savoy Cocktail Book. A later optional egg white lends it a silky, foam-capped finish.
Shaken · Coupe · None
add
Add gin, triple sec, fresh lemon juice (and egg white if using) to a cocktail shaker.
shake
If using egg white, dry-shake without ice first to build foam, then add ice and shake again; otherwise shake well with ice until chilled.
strain
Double-strain into a chilled coupe or cocktail glass, served straight up with no ice.