If you cool the ribs in their coiled state they are much harder to sauce and barbecue or broil to finish, so remove them from the pot and lay flat on a baking sheet to cool. Then you’ll do a quick release of pressure. With a 20-minute cook time and 15 minutes to come to pressure, the ribs will cook for a total of about 35 minutes. Instead, roll up the ribs and stand them up inside the pressure cooker on a trivet. Don’t cut the ribs and stack them for cooking in the Instant Pot - they won’t cook evenly. Turn steam release handle to SEALING position. Cover cooker with lid, and lock in place. Stand ribs on their long edges on rack in cooker, curling the ribs as needed to fit. Cover cooker with lid, and lock in place. Stir together sugar, salt, pepper, mustard, paprika, chile powder, and garlic powder in a small bowl coat ribs evenly with mixture. Air fry the second batch of BBQ ribs in Instant Pot. You can open the lid to check the progress). Press 'Airfry' button, set Temperature to 400F and Cooking Time to 15 minutes (takes roughly 9 - 11 minutes + preheat time. Here is where you can customize the flavor of your ribs and season them directly with the smoked salt. Stand ribs on their long edges on rack in cooker, curling the ribs as needed to fit. Layer ribs on the air fryer tray in Instant Pot. Place the Air Fryer lid on top and set to Roast or Broil at 400 F / 204 C for 10-15 minutes, or until ribs and sauce start to brown and caramelize. Then insert the basket into the clean Instant Pot inner pot. Allow the pressure to naturally release completely (about 15 to 20 minutes). Stand the ribs inside the Air Fryer basket. A dry rub is best for seasoning these ribs because the pressure cooker will essentially steam them - sort of washing away any wet seasonings on the ribs. For spare ribs: Cook on high for 35 minutes. With the bones facing up, slide a butter knife under the membrane between two rib bones until you can grip the membrane (a paper towel helps maintain the grip) and slowly pull it away like pulling off a label on a jelly jar. No length of cooking will soften or tenderize it, so you’ve got the peel it away before you season the ribs. Pork ribs have a thin layer of membrane that line the bone side.