In a heavy saucepan, whisk together eggs, sugar and salt. Gradually add 4 cups milk; cook and stir over low heat until a thermometer reads 160°-170°, about 30-35 minutes. Do not allow to boil. Immediately transfer to a large bowl.

Stir in vanilla, nutmeg and remaining milk. Place bowl in an ice-water bath, stirring until milk mixture is cool. (If mixture separates, process in a blender until smooth.) Refrigerate, covered, until cold, at least 3 hours.

To serve, beat cream until soft peaks form. Whisk gently into cooled milk mixture. If desired, sprinkle with additional nutmeg before serving. Yield: 12 servings (about 3 quarts).