300 ml milk
1/2 vanilla pod
15 ml/1 tbsp caster (superfine) sugar
2 egg yolks
Put the milk in a saucepan with the
vanilla pod. Bring to the boil and leave to infuse for 10 minutes.
Remove the vanilla pod and stir in the sugar. Bring almost to the
boil. Whisk the egg yolks in a basin. Whisk in the hot milk, then
strain back into the saucepan. Heat gently, stirring all the time with
a wooden spoon, until the mixture is thick enough to coat the back of
the spoon. Test by lifting the spoon out of the custard and drawing a
finger through the mixture on the spoon: if it leaves a clear line,
the sauce is ready. Do not allow the mixture to boil or the custard
will curdle. Serve hot or sprinkle with a little extra caster sugar to
prevent a skin forming and leave until cold.