Heat grill to high. Lay the prosciutto out on a large baking sheet and sit a turkey steak on top, crossways. Spread the turkey with the pepperonata, then top with 2 slices of mozzarella, a few basil leaves and some seasoning. Fold the ends of the prosciutto around the cheese to enclose. Grill for 10 mins until golden and cooked through. Leave to rest for 2 mins.
Cut the ciabatta into 4 or the rolls in half, then toast under the grill. Top with salad leaves, then sit the turkey on top and serve.