Place wrapping paper on the bottom of the springform pan and tighten the ring around it. Cut off the excess paper. For the cake base, beat eggs and 0.5 cup sugar until almost doubled in volume. The mixture should look white. Mix flour with baking powder and fold in.
Pour the batter into the pan and bake at 180 degrees convection for about 50 minutes.
It is best to bake the base a day in advance. Cook the pudding with 4 tablespoons of sugar according to the instructions on the package. Let it cool down, stirring it again and again. Butter and pudding must be at the same temperature (room temperature).
Beat the butter until creamy. Add the pudding by the spoonful. Cut the cake base in two crosswise. Spread the first cake layer with buttercream, place the second one on top and spread with warm jam. Cover with the third layer. Now spread buttercream all around the cake. Melt the chocolate and carefully stir in the remaining buttercream.
Decorate the cake with it. Press on the chocolate sprinkles with a spatula. Tip: The best way to decorate the cake is to place it on an upside-down pan, as it is also easier to turn for decorating.
