Preheat the broiler to high. Heat the oil in an ovenproof frying pan and fry the chicken over a high heat until browned all over. Add the dried herbs and passata and season well with salt and pepper, then add the zucchini spaghetti and warm through until a little softened.
Mix the cheeses with the breadcrumbs and scatter all over the top of the pan. Pop under the broiler for 4 to 5 minutes until golden and bubbling.