Many recipes that call for this ingredient actually specify Demerara syrup, especially tiki-style cocktails. Demerara syrup is made from a large-grained, crunchy raw sugar from Guyana (which used to be a Dutch, and then British, colony by the name of Demerara).
But if you can’t find Demerara sugar, or don’t have access to any premade syrups, you can make a perfectly decent substitute with regular brown sugar.
Simply combine an equal amount of water and brown sugar (or Demerara sugar, or any raw sugar), bring to just below a boil, stir until the sugar granules dissolve completely, let cool, and store in a jar or condiment bottle for up to a few weeks in the fridge.
