5 oz. finely cubed Gruyere cheese
5 oz. finely cubed Fontina cheese
1 3/4 c. finely grated Parmesan cheese
5 oz. coarsely grated Mozzarella cheese
1 1/2 tbsp. flour
1/4 c. butter
1 c. milk or light cream
1 lb. shell macaroni

First prepare all the cheeses, grating and cubing as specified, and then toss the Gruyere, Fontina and Parmesan with the flour, leaving the Mozzarella separate.

Heat the butter and milk or cream in a large, heavy-bottomed saucepan until the butter is melted. Stir in the 3 combined cheeses, bit by bit, and continue stirring gently with a wooden spoon until you have a smooth sauce. Keep it hot over a very low flame, and give it an occasional stir while you boil the pasta.

Cook the pasta in a large quantity of boiling water until it is al dente, 15 to 20 minutes. Drain it and immediately transfer to a large serving bowl which has been warmed in the oven. Pour the cheese sauce over the macaroni and stir quickly with 2 spoons. At the last instant, just before serving, stir in the Mozzarella quickly - do not overdo the stirring, for pasta cools quickly. Now serve at once onto heated plates. Serves 4.