Bring 200 ml milk with the vanilla sugar and the sugar to the boil. Meanwhile, beat the egg yolks and mix the cornstarch with the rest of the milk. When the milk and sugar boil, take the saucepan off the stove and stir in the egg and cornstarch until a creamy mixture is formed. Pour into two dessert bowls, allow to cool a little and serve.
If you want, you can sprinkle some sugar on it and caramelize it with a bunsen burner.