Bring the water and sugar to the boil and cook for 5 minutes.
Beat the egg yolks until pale and fluffy. Add the syrup to the egg yolks. Transfer to a double boiler or into a heavy based pan inside a larger pan with a little water in. Heat until the mixture is thick enough to coat the back of a spoon, stirring all the time. Allow to cool.
When cool add the cream, the Green Chartr