In the dish, mix the bell pepper strips with the onion, the Provençal herbs, and some salt and pepper to taste. Add ½ tablespoon olive oil to the mixture.
Cut the pork tenderloin into four pieces and rub with salt, pepper and mustard. Thinly coat the pieces with olive oil and place them upright in the dish on top of the pepper mixture.
Place the bowl in the basket and slide the basket into the airfryer. Set the timer to 15 minutes and roast the meat and the vegetables.
Turn the meat and mix the peppers halfway through the preparation time. Delicious with mashed potatoes and a fresh salad.