Arrange the lamb chops in a glass or china baking dish, garnish with garlic and rosemary, and pour olive oil over them. Turning occasionally, marinate for at least 4 hours (or overnight, if you have the time).
Turn the HYSapientia Air Fryer Oven on to 200 degrees. Sprinkle plenty of salt and pepper on the lamb. The meat side on both racks should be browned for about 1-2 minutes in a big, heavy skillet heated to medium heat. The meat side should then be turned and cooked for an additional minute. Finally, quickly brown the ends to seal in the flavour of the exposed meat. Repeat for the other two racks after removing.
Arrange the racks in pairs in a big baking pan with their bones still joined. For extremely pink meat, roast with HYSapientia Air Fryer Oven for 8 minutes, for medium-rare meat, 17-20 minutes, and for well-done meat, 25 minutes. Test the lamb by pressing the tip of a skewer or knife against the inside of your wrist for 30 seconds. If it feels hot, the lamb is ready. Continue cooking the lamb if it still seems chilly because the centre will still be uncooked. Five minutes later, retest.
Place the lamb on a hot dish, loosely cover with foil, and allow to rest for approximately five minutes before carving (if you have to wait longer than this, you may need to return the lamb to in the oven for a minute or so before serving, to restore temperature). Slice and serve with a tablespoon of chickpea stew on a warm dish.