Just recently, I have become enamored with a new rum in the store from Guyana called El Dorado Original DARK Superior Demerara. It is basically from brown, or partially refined, sugar – and is wonderfully tasty.
Actually, it is so rich, that I prefer it as an additive to Cruzan white (or equivalent) in a ratio of about 1 part dark to 3 parts white. Just start with a glass of ice and pour in the white rum and top off with this Demerara, adding a splash of mojito mix if you like and you have a beautiful drink that tastes innocent, but does the job!
Remember – this is a tip from an experienced engineer who would not steer you wrong!