How to Make It
In a small saucepan, combine the guava paste with the vinegar, rum, tomato paste, lime juice, soy sauce, Worcestershire sauce, ginger, scallion, garlic and water and bring to a boil. Simmer over low heat, stirring occasionally, until reduced to 1 1/4 cups, about 15 minutes. Season the sauce with salt and pepper.
The barbecue sauce can be refrigerated for up to 5 days.
Guava paste is usually sold in flat metal cans. It is available at many supermarkets as well as at Latin markets.