Heat up the milk. Beat the egg yolks and sugar in a bowl. Pour in a little boiling-hot milk, beating all the time, then pour in the rest of the milk and blend Return the mixture to the saucepan and leave to thicken, stirring continuously. Do not allow the cream to boil Once it coats the back of the spoon it is cooked. Leave to cool for a while. Add the cocoa and whip the mixture.Add the fresh cream and whip again.Leave the cream to cool before pouring into the ice-cream churn for freezing.