- Preheat the oven to 200 ° C (convection 180 ° C) and cover a rectangular baking sheet (approx. 25 x 35 cm) with baking paper.
- For the dough, put the eggs with the sugar and vanilla sugar in a mixing bowl and whip for about 6 minutes until creamy.
- Mix the flour with the baking powder, add and stir in well.
- Now stir the oil into the dough, then mix in the seltzer.
- Next, place the dough on the baking sheet and spread it evenly.
- Then bake on the middle rack in the preheated oven for about 20-25 minutes. Take out the baking sheet and let cool on a wire rack for about 30 minutes.
- In the meantime, wash the plums, pat dry, cut in half, remove the stones and quarter the plums. Sprinkle the plums with cane sugar and let stand for 30 minutes.
- Now distribute the plums on the cooled cake. Whip the cream and mix with the sour cream.
- Finally, carefully place the cream mixture on the Seltzer cake with plums Spread and smooth out, sprinkle with chocolate sprinkles and serve.