Mix flour, starch, baking powder, 375 g icing sugar and vanillin sugar in a mixing bowl. Add eggs, cooking oil and vanilla sauce. Mix with the whisk of a hand mixer to a smooth dough.
Line the bottoms of 2 springforms (approx. 20 cm and 26 cm Ø) with baking paper. Put 2/3 of the dough into the larger springform pan and put the rest of the dough into the small springform pan. Bake the forms one after the other in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for about 50 minutes in the small springform pan and bake the larger one for about 60 minutes. Cover the bases with aluminium foil after each approx. 25 minutes baking time. Remove from the oven and let each cake cool down on a cake rack for about 3 hours.
Stir the pudding powder, 150 g sugar and 100 ml milk until smooth. Bring 400 ml milk to the boil, stir in the pudding powder, bring to the boil and simmer for 1 minute. Remove from the stove. Pour into a bowl, cover directly on the surface with cling film. Let it cool down
Whisk 250 g butter with the whisk of the hand mixer for approx. 15 minutes until white-creamy. Stir the pudding and raspberry jelly until smooth. Stir in both bit by bit by the spoonful. Finally stir in some food colouring. Remove the base from the mould and cut through horizontally once each time. Spread about 1/3 of the buttercream on the smaller cake base, place the second cake base on top and press down gently. Spread the rest of the cream on the larger cake base, place the second cake base on top and press down lightly. Chill both cakes for at least 1 hour.
Whip 250 g butter with icing sugar until white-creamy. Spread a thin layer of butter cream on both cakes and chill for another 20 minutes. Roll out both fondant covers thinly to 38 cm Ø. Cover both cakes with a fondant cover and press lightly. Cut off protruding edges
Quarter the remaining fondant. Leave 1/4 white and colour 1/4 each with food colouring in three different shades of pink. Roll out thinly on a piece of cling film and cut out about 30 flowers each with a cookie cutter (approx. 2.5 cm Ø). Use a modelling tool (small ball) to press a small bulge in the middle of each flower and decorate the cake with it. Keep the cake in a dry and cool place until serving.