In a large pot, cook the paste al dente in salted boiling water. Drain and pour a third of the pasta into a buttered shallow baking dish. Sprinkle with Sbrinz. Salt and pepper. Pour in another third of the pasta and sprinkle with Emmental. Salt and pepper. Pour in the last of the pasta and sprinkle with Gruyère. Salt and pepper. Finally, add a few pats of softened butter. Brown in the oven (15 min) at 240°C. Accompaniment Chianti or Bardolino