In a small bowl mix together the brown sugar, chili powder, smoked paprika, garlic powder and salt and pepper.

Cut the pork Shoulder into 6 to 8 big chunks. Liberally season both side of each chunk of pork with the prepared dry rub.

Turn the Instant Pot on the ‘Sauté’ mode. Add the olive oil and let it heat up for a couple of minute.

In batches, add the 3 to 4 pork chunks and let it cook for 3 to 4 minutes on each side or until both sides gets a golden sear. Transfer the seared meat in to a clean plate and continue searing the rest of the meat chunks.

Add the chicken stock and the BBQ sauce to the instant pot and return the seared pieces of the meat to the instant pot too.

Turn off “Sauté” mode. Put the lid on, making sure that the pressure valve is in the “Sealing” position.

Select the “Pressure Cook” mode. Adjust the time, with the “- / +” to 1 hour.

When Instant Pot beeps, let the pressure release the natural way for 30 minutes and then using a thick tea towel, turn the pressure valve to “Venting” position to do the quick release.

Using a slotted spoon, transfer the pork chunks to a large bowl and shred it using two forks.

Meanwhile, skim the fat from the liquid accumulated in the Instant Pot using a spoon or a ladle or a fat separator.

Then turn on the ‘Sauté’ mode for 20 minutes and let liquid in the instant pot simmer and thicken.

Add the shredded pork back in the IP to soak up the BBQ sauce.

Serve immediately over toasted hamburger buns, topped with crunchy coleslaw.

Refrigerate the leftovers.