The best French door air fryer toaster oven is the Breville Smart Oven Air. It has a large capacity and can accommodate a whole chicken or roast. The air fryer function uses convection technology to circulate hot air around food for even cooking. There are 10 pre-set functions, including an air fry function, so you can cook just about anything in this oven. The LCD display makes it easy to navigate the menu and the slow cook function is perfect for making stews and casseroles.