For the vanilla sauce, remove 3 tablespoons of milk from the milk. Stir with half of the sauce powder (approx. 3 level teaspoons) and 2 tablespoons of sugar until smooth. Bring the rest of the milk to the boil and stir in the sauce powder.
Simmer for a minute. Cover and chill.
Drain the cherries in a sieve, collecting the juice in a small pot. Take off 2 tablespoons of juice, stir with the rest of the sauce powder and 1 tablespoon of sugar until smooth. Boil up the rest of the juice, stir in the sauce powder and simmer for 1 minute.
Fold in the cherries. Cover and keep warm on the switched off stove.
For the croutons, roughly chop the hazelnuts. Roughly dice the buns. Heat butter in a pan. Fry the buns in it until crispy all around. Fry the nuts briefly. Sprinkle everything with 3 tablespoons of sugar and caramelise while turning.
Arrange croutons with hot cherries and vanilla sauce.