Preheat your oven to 200ºC/400ºF/gas 6. Cook the macaroni in a pan of salted boiling water 2 minutes short of the timing on the packet instructions, then drain in a colander and reserve a little of the cooking water. Heat the butter in a large heavy-based frying pan. When it starts to foam, add the marjoram or oregano and fry for a minute until it starts to crisp up, then turn off the heat. Add your cooked pasta to the marjoram or oregano butter, along with a couple of spoonfuls of the reserved cooking water and the Parmesan, fontina or taleggio and mascarpone. Return to a medium heat and toss and stir around until most of the cheese has melted and you have a lovely gooey sauce – you may need to add a little more of the reserved cooking water. Season to taste, then tip it all into an earthenware dish. Grate over the nutmeg, tear over the mozzarella and sprinkle over the extra Parmesan. Bake the macaroni cheese in the preheated oven for about 10 minutes, finishing up with a quick whack under the grill, until golden brown and crispy on top.