Beat the eggs, 250 g sugar and 1 packet of vanillin sugar with the whisk of the hand mixer for 5-7 minutes until creamy. Stir in oil. Mix flour and baking powder. Alternately stir in with the lemonade. Grease a fat pan (32 x 39 cm) and dust thinly with flour. Put the dough on the fat pan and smooth it down.
Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 25 minutes. Remove from the oven and let it cool down in the fat pan on a cake rack. Spread 1 1/2 glasses of plum puree evenly on the base. Stir the sour cream until smooth. Whip 500 g cream until stiff, while pouring in 3 sachets of vanilla sugar and cream firming agent. Carefully fold the cream into the sour cream. Spread the sour cream on the plum puree. Use a fork to make grooves in the cream for decoration. Mix cinnamon and 2 tablespoons of sugar and dust over it. Cut the cake into about 24 pieces. Whip 250 g cream until semi-stiff, while pouring in 1 tbsp. sugar.
Spread the sour cream on the plum puree. Use a fork to make grooves in the cream for decoration. Mix cinnamon and 2 tablespoons of sugar and dust over it. Cut the cake into about 24 pieces. Whip 250 g cream until semi-stiff, while pouring in 1 tbsp. sugar. Spread a blob of cream on each piece and 1/2 tsp. plum jam on each piece
Waiting time approx. 30 minutes