Mix chili powder, onion powder, garlic powder, salt, and black pepper. Rub on pork chunks.
Set Instant Pot to Sauté, add olive oil, and heat for a minute.
Brown pork chunks in Instant Pot, then set aside.
Combine barbecue sauce, chicken broth, apple cider vinegar, brown sugar, and Worcestershire sauce in Instant Pot.
Add browned pork to Instant Pot, submerging in sauce.
Secure lid, set pressure release valve to Sealing, and cook on high pressure for 1 hour 30 minutes.
Allow natural pressure release for 15 minutes, then vent remaining pressure.
Remove pork, shred with forks.
Optional: thicken sauce by simmering on Sauté for 5-10 minutes. Pour over shredded pork.
Serve and enjoy!