Kentucky style BBQ is centered around sauces and mops made with Worcestershire and apple cider vinegar as the base. Hence, commonly called "black sauce."
Another identifier of Kentucky cue is the common use of mutton. That's because Kentucky, at one time, was the largest sheep producer in America.
Here is my take on a classic Kentucky black barbecue sauce:
1 cup Wocestershire
1/2 cup apple cider vinegar
1/4 cup (6-oz can) tomato paste
1 tsp allspice
1/4 tsp cinnamon
4-5 tables brown sugar or powdered honey
Whisk all ingredients together in a saucepan. Bring to boil, lower heat to simmer, and cook until reduced by about one third.
For a mop, combine equal parts Worcestershire and apple cider vinegar. This can be used as an injection as well as a mop.