Batiste starts on the Caribbean island of Marie Galante, and this Island Punch is our nod to a traditional island-libation, the Ti Punch.  The consistent features are: a small (or large) tumbler, Rhum, lime and sugar. Some grind lime with sugar and add a shot of Rhum, mix and drink. Others use sugar syrup, some add ice. Others eat the lime, throw sugar at each other and then drink from the bottle (that often happens much later and when all the nice people have gone home).