In a deep metal container, mix the cold milk, sugar, coconut flakes, vanilla sugar, starch, stir well.
Put the mixture on low heat to come to a boil, while stirring nonstop. Once thickened, add the butter and stir until it dissolves.
While still hot, pour into small bowls, cover with plastic wrap and leave to cool in the fridge.
Before serving, sprinkle with ground hazelnuts and coconut flakes.