SHAKE all ingredients with ice and fine strain into chilled glass.
Gin and mint with a splash of lime. Refreshingly balanced.
This vintage cocktail is purported to have originated at New York's Twenty-One Club. A long version served over crushed ice is said to have come from the southside of Chicago during Prohibition where it was drunk by the Southside mobsters, while on the other side of town hoodlums enjoyed the Northside (gin and ginger ale).