Trim any excess fat off of the pork butt/shoulder and cut into 4 large chunks.
Mix all of the ingredients of the dry rub together and rub all over the pork chunks.
Set the instant pot to sauté for 10 minutes. Work in batches if necessary and sear all sides of the pork chunks. Set aside
Deglaze the pot with chicken broth and vinegar and add the pork back in. Add in ⅓-½ of the barbecue sauce. Do not stir
Seal the pot and set on manual heat for 50 minutes-1 hour depending on the weight of your pork.
When it is done cooking, allow the pressure to release naturally for 10 minutes, then hit the manual release button after if needed.
Using a fork, or bear claws, shred the pork. Add in remaining barbecue sauce if desired, or set aside for serving.
SERVING SUGGESTION: Pile up while hamburger buns with the pulled pork. Top with cabbage slaw, dill pickles, extra BBQ sauce, and serve!