Shake and strain into a double old-fashioned glass with an ice cone encased straw.
The dark rum should be Jamaican: Myer's, Coruba, or Appleton 12. Straining onto the rocks would be a good alternative to an ice cone. An ice cone is made by packing shaved ice into a pilsner glass, poking a chopstick through for the hole, and freezing. I add the soda water after shaking.
Beachbum Berry Remixed