Bring salted water to a rolling boil for the pasta and cook to package directions for al dente pasta.
Slice prosciutto ham into thin strips across. Separate ham ribbons and loosely pile them up and set aside.
Preheat a large skillet over moderate heat. Drain the pasta. Add the butter to the pan and melt. Add half-and-half to the melted butter. Stirring constantly, add cheese and cook sauce 1 minute. Season with nutmeg, pepper, and a pinch of salt. Turn off heat under sauce and add pasta to the skillet. Toss pasta until sauce coats the noodles evenly. Add prosciutto ribbons and toss to evenly distribute them. Mangia!