What does adding dark rum give to a fajita stir-fry?

Question

I'm looking at a recipe for a fajita stir-fry that includes an optional 2 tbsp of dark rum. The introduction for the recipe mentions,

Latin spices combined with the optional kick of dark Jamaican rum make an interesting marriage of flavors.

What does the rum offer to the recipe? I ask because I'm not sure I want to buy a whole bottle of dark rum just for one recipe.

Answer

In the Caribbean and other Rum producing areas, you find Rum in all sorts of recipes

It is sometimes an unusual flavour pairing, but not necessarily bad. In savoury cooking it adds a semi-burnt sweetness, more like toffee or butterscotch than straight Rum

Caribbean and Mexican cooking is well blended and harmonious with many common ingredients (chilli, coriander, avocado etc.)

Considering the popularity of spicy jerk meat and Rum, the Rum Fajitas would be an interesting experiment

Check more discussion of this question.