Preheat the oven to 180 degrees top / bottom heat.
Beat eggs, sugar and vanilla sugar until frothy. Then stir in the cream carefully. Mix the flour, baking powder and salt in a separate bowl.
Then sift the flour mixture into the cream mixture and stir in briefly. Then briefly stir in the mineral water and lemon juice. Transfer about half of the dough and work in the persimmon powder there. If the dark dough becomes too thick, simply add another shot of mineral water. Put alternately a tablespoon of dark and light batter into the muffin molds.
Bake the muffins for about 20-25 minutes and then let them cool down. Please do not forget to test your chopsticks after baking. Melt the couverture in a water bath and coat the muffins with it.