Cream fat, sugar and vanilla sugar. Stir in eggs bit by bit. Mix flour and baking powder, sieve onto the fat egg mass and fold in. Stir in milk. Pour the dough into a greased springform pan (28 cm Ø) and bake in a preheated oven (electric cooker: 200 °C/ gas: level 3) for approx. 30 minutes.
Allow to cool in the mould. In the meantime, drain the rasped pineapple and collect the juice. Stir pudding powder and 5 tablespoons of water until smooth. Bring the pineapple and lemon juice to the boil, stir in the pudding powder and bring to the boil again briefly.
Stir in the grated pineapple and spread the cake base with it. Chill for about 15 minutes. Drain the pineapple slices and cut into small cubes, except for 3 slices. Soak gelatine in cold water.
Heat lemon juice, sugar and vanillin sugar in a pot. Squeeze out the gelatine and dissolve in it. Stir mascarpone and yoghurt until smooth. Stir in the dissolved gelatine drop by drop and keep cool.
Whip the cream until stiff. As soon as the mascarpone cream begins to firm up, fold in approx. 2/3 of the cream and the pineapple cubes. Spread the cream on the pineapple grater, except for a little bit for spreading. Put in a cool place for about 1 hour.
Remove the edge of the springform pan and spread the remaining cream on the edge of the cake. Use a cake comb or fork to press grooves into the edge. Pour the remaining cream into a piping bag with a star nozzle and squirt tuffs onto the cake.
Cut the remaining pineapple slices into pieces and place them in front of the tuffs. Sprinkle cake with brittle.