Dark and Stormy

A Dark and Stormy (or Dark 'n' Stormy) is an alcoholic highball style cocktail originating in Bermuda, where it (along with the Rum Swizzle) is a national drink. Dark 'n' Stormy is a registered trademark of Gosling's Brothers Limited in Bermuda. The trademark only allows it to be made with a measure (1.5oz) of Black Seal Rum and Bermudian based Barritt's ginger beer to taste. It is optionally accompanied by a slice of lime. Dark 'N' Stormies can also be made with Golden Rum, for example Appleton Estate, and can also be made with ginger ale.
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1 part black rum
1 part ginger beer (non-alcoholic)

Serve in lowball glass.