Rinse ribs and pat dry. Remove the thin membrane from the back of the ribs.
Cut slab into 4-6 pieces (enough so they fit into the Instant Pot on their sides) and coat with dry rub massaging the rub mixture into the meat.
Place trivet in the bottom of your Instant Pot.
Add water and liquid smoke.
Set ribs upright on the trivet (so they are not stacked on top of one another, rather next to eachother.
Secure the Instant Pot lid, select manual pressure and set the timer for 25 minutes.
Once done, allow the Instant Pot to natural release for 5 minutes.
Carefully open sealing valve to release remaining pressure.
Brush with barbecue sauce (or olive oil/salt/pepper for dry ribs) and broil or grill until slightly charred.