1) In a 4-cup glass measuring cup, pour 1-1/2 cup milk.
2) Stir in sugar and cook in microwave on the highest setting for 2 minutes.
3) Combine egg yolk with cornstarch and 1/4 cup of cold milk.
4) Add the hot milk and sugar and cook on highest setting for 1 minute.
5) With a wire whisk stir the mixture gently.