Fill glass with ice and POUR absinthe and Angostura over ice. TOP with chilled mineral water and leave to stand. SHAKE gin, vermouth and orange water with ice. DISCARD contents of standing glass and fine strain shaken drink into washed glass.
Orange zest twist
Aromatic, very dry and very serious - yet has a frothy head.
Adapted from a recipe in Harry Craddock's 1930 Savoy Cocktail Book.