I'm a fan of Old Fashioneds, and a huge fan of rum, so when I heard about a rum-based old fashioned I had to try it.
A dash or two of bitters
A splash of simple syrup
2 oz spiced rum
Top with a splash of lime juice
Garnish with a lime wedge and a lime swath
I introduced it to some friends at a party and it was an immediate huge hit, though I have to give much of the credit to the rum! There are plenty of options for bitters out there, experiment to see what would go best!