Crème pâtissière

• 1 egg yolk
• 150 ml/¼ pint milk
• 1

In the top of a double saucepan, whisk the egg yolk into the milk. Add the cornflour mixed with water 180 and sugar and cook over lightly simmering water, stirring continually with a wooden spoon, until the sauce is thick enough to coat the back of the spoon. Do not let the mixture come to the boil. Remove from the heat; cool and use as directed above.