Very basic stuff: cup of apple cider vinegar, half-cup of ketchup, Worcestershire sauce, brown sugar, salt, butter, smoked paprika, and some chili powder. Simmered it in a saucepan for a couple of hours and poured it over the slow-cooked chicken. Worked out pretty good; I am starting to delude myself that I maybe know how to cook things.
Yes, you may take this as an invitation to start a BBQ War in comments. But, to quote Bob Heinlein: if any ears are ripped off you will be required to give them back at the end of the fight.