PLACE sugar cube on a slotted absinthe spoon resting across the top of the glass. POUR the absinthe over the sugar cube into the glass. LIGHT the absinthe soaked cube and leave to burn and caramelise. Using a bottle of chilled mineral water with a small hole in the cap, DRIP water over what's left of the sugar so it dissolves and drips into the glass. Add ice, stir and serve.
More about the theatrics involved in its making than the taste of the finished drink.
This supposedly bohemian method of serving absinthe came back in to being in 1998 with the UK launch of Hill's Absinthe. Accordingly, if you are going to make this drink then it is best to use a Czech style absinthe such as La Fée Bohemian.