A well-known citizen of Florence in the 1920s, Count Camillo Negroni, once asked the bartender at the old Casoni Bar to make him an Americano (Campari and sweet vermouth) with the addition of gin. He liked the result and ordered it wherever he went, and soon the drink took on his name.
3 oz. gin (preferably Bombay Sapphire)
3 oz. Campari
3 oz sweet vermouth
Slice of orange, halved
1. Combine gin, Campari, and vermouth in a large tumbler. Fill two glasses with ice, pour half of the negroni into each, and garnish with half the orange slice.