Melt the butter in a saucepan, then add the sugar and let it caramelize while stirring. When the caramel has a golden yellow color, it is carefully extinguished with the cream and stirred until it has completely dissolved in the cream.
Then add the vanilla sugar and a pinch of salt. Dissolve the cornstarch in a little milk in a bowl. Make sure that there are no lumps. Now add the milk-starch mixture to the cream and bring to the boil until the pudding has the desired consistency.
The pudding tastes very good both warm and cold. If you like, you can replace the cream with milk.