1Cook tortellini in large pot of boiling salted water until barely tender, stirring occasionally to prevent sticking. Drain thoroughly.
2Meanwhile, bring cream to boil in heavy large saucepan. Reduce heat. Add nutmeg and simmer until slightly thickened, about 8 minutes.
3Return tortellini to pot. Add warm cream, Parmesan, peas and prosciutto. Simmer over low heat until tortellini are tender and sauce thickens, stirring occasionally, about 4 minutes. Season with salt and pepper.