Separate the egg yolks from the whites. Next, add the baking soda to the yoghurt, stir and leave it to bubble.
Beat the yolks very well with a mixer, then add the sugar and stir well.
Add the milk, stir well, then add the flour which you've sifted with the baking powder.
Stir once again, add the vanilla sugar and butter (butter needs to be at room temperature).
Once the mixture is ready, pour it into a buttered oven dish and bake in a 356°F (180 °C) oven until ready. While it's baking, beat the egg whites with 2-3 tbsp sugar into snow.
Once the cake dough is fully ready, pour the cherry jam on top, then the beaten whites on top of it. Return to the oven for the egg whites to turn pink.