Trim excess fat from the pork shoulder.
Mix the brown sugar, paprika, garlic powder, onion powder, cumin, salt, and black pepper in a bowl.
Rub the spice mixture all over the pork shoulder.
Place the pork in a slow cooker, fat side up.
Pour the apple cider vinegar and chicken broth into the slow cooker.
Cover and cook on low for 8 hours or high for 4 hours until tender.
Once cooked, remove the pork and let it rest for 15 minutes.
Shred the pork using two forks, discarding any large pieces of fat.
Mix the shredded pork with barbecue sauce to taste.
Serve immediately or keep warm until ready to serve.