Porcino is the Italian word for the mushroom that the French call the cep, Boletus edulis (called 'penny bun' in Britain). This mushroom is generally agreed by connoisseurs to be among the finest eating mushrooms.
A related variety, Boletus aureus, is called the 'porcino nero', or black porcino, in Italy. Porcini make great eating and are highly valued by chefs and gourmets. They can also be very expensive, particularly when fresh, although dried porcini tend to be better value. Use fresh or dried porcini in pasta dishes, risottos or to give a deep, woodsy flavour to stews and casseroles.