Halve the chicken lengthways to create four fillets, then cover with baking parchment and bash using a rolling pin or base of a saucepan until they’re all an even thickness.
Tip the flour onto a plate and pour the egg onto a separate plate. Combine the panko and parmesan on a third plate. Coat the chicken in flour, then dip in the egg and finally coat in the panko mix. Repeat until all the chicken is coated, then place in your air fryer and cook at 180C for 15 mins, or until golden.
Spoon 1-2 tbsp of tomato sauce onto each piece of chicken then place a slice of mozzarella on top. Put back in the air fryer and cook for a further 5-10 mins until the mozzarella has turned golden and the chicken is cooked through. Serve with spaghetti, more tomato sauce, cracked black pepper and a sprinkling of torn basil leaves.