Mix egg yolks, whole egg, sugar and lemon rind well. Scrape the inside of the vanilla bean into the mixture and add the wine.
Put the mixture in the top part of a double boiler and cook it over simmering water, stirring constantly, till the mixture thickens. (If you are an experienced cook, you can do this over direct heat, but you must stir the mixture all the while.)
Serve as a sauce for desserts, for instance Golden Dumpling Cake. Or serve as a cream dessert accompanied by little cakes or cookies.
If you like a thicker mixture, mix ½tablespoon flour with the egg yolks in the beginning. Cook the wine cream and then mix in 2 egg whites, beaten stiff.