In a small bowl, combine smoked paprika, garlic powder, onion powder, brown sugar, salt, black pepper, cumin, and cayenne.
Rub the spice mixture all over the pork shoulder.
Place the pork in a slow cooker and pour in chicken broth and apple cider vinegar.
Cover and cook on LOW for 8–10 hours or HIGH for 5–6 hours, until the meat is tender and shreds easily.
Transfer pork to a large bowl and shred with two forks.
Return shredded pork to the slow cooker and toss with the juices.
Serve warm with barbecue sauce on buns, in tacos, or over rice.