Set Instant Pot to Sauté mode, then heat the oil.
1 tablespoon olive oil
Coat the ribs on all sides with the seasoning mixture and brown sugar, massaging it in while the oil heats.
3 lbs boneless country style pork ribs, 1 tablespoon brown sugar, ½ cup Cajun seasoning
Once the ribs are coated, and the oil is hot, sear the ribs on all sides (you will have to do this in batches) then remove the ribs and set them off to the side.
Add the sliced onions to the Instant Pot and sauté them in the leftover oil and seasoning.
1 onion
Deglaze the Instant Pot with the broth and scrape any meaty bits off of the bottom. (This will prevent a burn message.)
½ cup chicken broth
Lay the ribs on top of the onions and cancel Sauté mode.
Place the lid on the Instant Pot and turn the vent to the "Sealing" position.
Cook the ribs at High Pressure for 45 minutes. (It will take about 15 minutes to come to pressure.)
When the cooking cycle is complete, allow the pressure to naturally release for about 15-20 minutes.
Carefully open the lid.
Move the onions and ribs to a bowl using a slotted spoon and shred the ribs up. You can serve them in big chunks or really tear them apart with a fork.
Mix some of the juices from the crockpot with the barbecue sauce and coat the ribs with it. (I like to only coat a portion of the ribs so I can save some of the meat for use in other dishes.)
½ cup barbecue sauce
Serve & enjoy!