500ml/18fl oz tomato passata
350g/12oz best quality thick spaghetti, such as gragnano or bucatini (or regular spaghetti)
salt and freshly ground black pepper
2 tbsp olive oil
100g/3½oz grated pecorino cheese (or Parmesan or any hard cheese), plus extra to serve
150g/5½oz guanciale di Amatrice (cured pork cheek or jowl), cut into half-matchstick pieces (or bacon instead)