custard powder and sugar in medium pan, add orange juice and water, stir
until combined. Stir constantly over medium heat for 3 minutes or until
mixture boils and thickens, boil for a further 1 minute. Add mascarpone,
lemon butter and Cointreau, stir until heated through.
Mascarpone is an Italian fresh cream cheese. It is extremely rich and
can be used as a substitute for cream. Available from delicatessens and
large supermarkets. Unsuitable for freeze.