Bring the milk and cream to the boil.
Whisk the sugar and egg yolks together and whisk into the just boiled milk and cream. Return to a gentle heat, stirring constantly, until the custard coats the back of a wooden spoon. Allow to cool.
When cool stir in the Grand Marnier, Orange Flower Water and lime zest to the custard. Place into ice cream machine or deep freeze. If using dee