White Lady (also known as a Delilah, or Chelsea Side-car) is essentially a sidecar made with gin in place of brandy. What makes it different from the simple gin sour is the switching of sugar for triple sec. The cocktail sometimes also includes additional ingredients, for example egg white, sugar, or cream.

The classic concoction is most commonly served in a Martini cocktail glass. When an egg white is added a champagne coupe is preferable; the silky foam clings more pleasingly to the curved glass.

It is disputed who originally invented the drink. There are at least two different opinions: first that it was devised by Harry MacElhone in 1919 at Ciro's Club in London. He originally used crème de menthe, but replaced it with gin at Harry's New York Bar in Paris in 1929.But The Savoy's Harry Craddock also claims the White Lady (gin, Cointreau, fresh lemon juice). The recipe appears in his Savoy Cocktail Book, published in 1930.

From White Lady cocktail -wiki

[[Recipe]]
Gin 60ml
Orange liqueur 15ml
Fresh lemon juice 15ml
Fresh egg white 1

Add all ingredients into a shaker with ice and shake.
Strain into chilled cocktail glass.

From Liquor.com -White Lady

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