Drain the cherries, collect the juice and fill up to 1/2 l liquid with water. Stir groats powder, 2 tablespoons sugar and 6 tablespoons juice until smooth. Boil up the rest of the juice and lemon peel. Stir in groats powder and bring to the boil again briefly.
Fold in the cherries. Leave to cool down a little. Remove lemon peel. Pour the groats into 4 dessert glasses and let them cool down
Stir yoghurt, 1 tablespoon sugar and vanilla sugar until smooth. Whip cream until stiff and fold in. Spread on the groats. Decorate with mint and citrus peel