Cut pork into 3-4 chunks, removing bone and excess fat.
Set the Instant Pot to sauté mode. While warming up, mix all of the dry spices with 1 tablespoon of the brown sugar.
Rub the sugar and spice mixture onto the chunks of pork.
When the Instant Pot reads HOT add the oil. Tilt the pot back and forth to evenly coat the bottom. Then place the seasoned meat chunks into the instant pot. Be sure to get an even layer of meat; you may need to work in batches.
Brown the meat on each side for 3-4 minutes. When all sides are brown remove the meat from the pot.
Add the water to the pot to deglaze. Use a flat spoon to scrape the bits off of the bottom.
Once the pot is deglazed, whisk in the vinegar, tomato paste, liquid smoke, and the rest of the brown sugar.
Place all of the browned meat back into the pot in an even layer. You may need to wiggle and squish them a bit to do this.
Pressure cook on high for 60 minutes and allow a natural release for 20 minutes.
At the end of 20 minutes release any remaining pressure. Remove the pork from the pot. Place onto a plate and shred with two forks.
Optional: you can use the juices left in the pot as a sauce, but depending on the cut of meat it may be very greasy.
Serve the shredded pork with your favorite sides and barbecue sauce, or with all of your favorites on a bun.
Notes
For a nice kick you can add ¼ teaspoon of cayenne pepper to the seasoning rub.
This reheats great and can be made the day before.
Reheating in a slow cooker is best (so that it doesn't dry out as easily) but it can also be reheated in the microwave or in a skillet. Be sure to save any juices from cooking to reheat the meat with if they aren't too greasy.
Refrigerate in an airtight container for up to 4 days or freeze for up to 6 months.