In a small bowl mix together the brown sugar, paprika, garlic powder, onion powder, salt, pepper, cumin and cayenne.
Season the cubed pork with the spices mixture and set aside.
In a medium bowl whisk together the apple vinegar, one cup of barbecue sauce, the hot pepper sauce (optional) and one cup of broth.
Turn Instant Pot to sauté setting. Add the olive oil and allow to get hot.
Add half of the cubed pork to the hot oil and santé for 5 minutes. Remove the browned pork to a plate and repeat with the remaining half of the pork for another 5 minutes
Turn Instant Pot off. Use 1/4 chicken broth to scrape the brown bits from the bottom of the Instant Pot ( IMPORTANT STEP).
Add all the cubed pork in the Instant Pot with the barbecue mixture.
Close carefully the lid and set to sealing.
Cook on manual high pressure for 40 minutes. Once the cooking time is up, allow the pressure to slow release naturally for 10 minutes. Then do a quick release.
Remove the meat from the Instant Pot and shred. Stir in the remaining 1 cup barbecue sauce.
Serve on a Buns with coleslaw (optional). Enjoy!