SHAKE first five ingredients with ice and fine strain into chilled glass. Carefully POUR grenadine into centre of drink so that it sinks to create a sunrise effect.
Orange zest twist
Although it spoils the sunrise effect, this drink is less tart if the syrup lying on the bottom is stirred into the drink (or, better, included when shaking).
Created in September 1930 by Tom Buttery at the Berkeley Hotel, London, England. There are now many versions of this classic drink (David Embury's 'The Fine Art of Mixing Drinks' lists three) but this is my favourite.