In a small bowl, mix brown sugar, smoked paprika, garlic powder, onion powder, and salt.
Rub the spice mixture all over the pork shoulder, ensuring an even coating.
Place the seasoned pork in the slow cooker and pour in the chicken broth and apple cider vinegar.
Cover and cook on LOW for 8-10 hours or HIGH for 5-6 hours until the pork is tender and easily shredded.
Remove the pork from the slow cooker and let it rest for a few minutes before shredding with forks.
Return the shredded pork to the slow cooker and mix with the juices for added flavor.
Serve on buns, over rice, or in tacos, drizzling extra sauce as desired.