1In 2-quart saucepan, heat eggnog and half-and-half over medium-low heat, stirring occasionally, until hot.
2In medium bowl, beat egg yolks, cornstarch and rum extract with wire whisk. Stir a small amount of the hot eggnog mixture into egg mixture, then gradually stir egg mixture back into eggnog mixture in saucepan. Continue cooking over medium-low heat, stirring constantly, until mixture just begins to boil and thicken. Immediately remove from heat.
3Pour into 6 small serving dishes. Sprinkle with nutmeg. Refrigerate at least 8 hours until well chilled and set.