Pat the ribs dry. Moisture is the enemy of a good crust.
Use paper towels and get them as dry as you can.
Preheat the air fryer to 375°F (190°C) for 5 minutes. A hot basket helps the surface sizzle right away.
Mix the rub. In a small bowl, combine salt, pepper, smoked paprika, garlic powder, onion powder, brown sugar, ground mustard, and cayenne (if using).
Oil and season. Toss ribs with olive oil. Sprinkle the rub all over, pressing it in so it adheres. Aim for even coverage.
Arrange in a single layer. Lightly spray the basket.
Place ribs in one layer without crowding. Work in batches if needed.
Air fry for 10 minutes at 375°F. This starts the browning and renders some fat.
Flip and cook 8–10 minutes more. Ribs should be nicely browned and around 165–175°F internally at this stage.
Glaze with BBQ sauce. Brush ribs with a thin layer of barbecue sauce.
Air fry 3–5 more minutes at 390°F (200°C). This caramelizes the sauce and crisps the edges. Target an internal temp of 190–200°F for the most tender, pull-apart texture on country style ribs.
Rest for 5 minutes. Tent loosely with foil.
This keeps juices in and the glaze tacky.
Garnish and serve. Add a sprinkle of herbs if you like. Serve with extra sauce on the side.