Combine the egg yolks, cornflour and caster sugar together in a bowl, mix until smooth.
Heat the milk in a saucepan until almost boiling.
Gradually pour the hot milk into the egg mixture, stirring all the time as you do so.
Now return the egg and milk mixture to the pan and cook over a low heat stirring constantly until thickened.
Remove from the heat and pour the thickened custard back into a bowl.
Sprinkle the surface with a little granulated sugar (this will prevent a skin forming) and allow cool.
When the custard has cooled completely, whip the cream in a large mixing bowl until standing in soft peaks.
Add the cool custard, chopped ginger and the ginger syrup.
Mix until evenly combined.
Pour into a shallow freezer proof container and chill for at least 2 hours before serving.
