Add the beef stock, bay leaves, and pork shoulder into the slow cooker. Cook on low for 6 hours or high for 4 hours.
Remove the cooked pork and the bay leaves from the slow cooker. Remove half of the liquid from the slow cooker. II find it best to do this with a liquid measuring cup.
Remove the bone from the pork shoulder if you used a bone in cut of meat.
Using a fork shred the pork and add it back into the slow cooker add the Barbecue sauce and mix well. Cook for an additional 30 minutes on low.