1: Fire up your Ooni pizza oven.
Aim for 415˚F (212˚C) on the stone baking board inside. You can check the temperature inside your oven quickly and easily using the Ooni Infrared Thermometer.
2: While your Ooni is heating up, season the leg of lamb with the salt, pepper and garlic powder.
Place on a foil-lined baking tray.
3: Once your Ooni reaches temperature, slide the tray into the oven while keeping it closer to the door to avoid too much radiant heat.
Spin every 15-20 minutes and cook for about an hour and a half to an hour and 45 minutes, or until the leg of lamb is medium to well-done.
4: Once cooked, remove the leg of lamb from the oven and cover with foil.
Leave it to rest for about 10-15 minutes. Serve while hot!