Put the flour, sugar, vanilla sugar and baking powder in a bowl and mix together. Add the soy milk and oil and stir well until a viscous dough is formed.
Grease the baking pan very well and fill it with the entire batter. Bake the cake for 25 minutes in the preheated oven at 180 ° C on the middle rack. The cake should be golden brown. Turn the cake straight out onto a cake plate and let cool down completely.
Distribute the fruits on the floor as desired, e.g., first spread the blueberries all around in a circle and then put the currants and blueberries in the middle, thick and thick.
Prepare the icing according to the instructions on the packet and carefully pour over the berries. Let cool down.