Knead flour, fat, sugar, vanillin sugar, egg yolk and salt to a smooth short pastry. Cover and put in a cool place for about 1 hour. Soak gelatine in cold water. Bring milk, sugar, egg yolk and lemon peel to the boil while stirring constantly. Pour into a bowl, squeeze the gelatine and stir into the hot milk. Put in a cool place for about 1 1/2 hours.
Roll out 3/4 of the short pastry on a greased springform pan (26 cm Ø). Bake in a preheated oven (electric: 200°C/ gas: level 3) for 10-15 minutes and let cool down. Roll out the rest of the short pastry and cut out cookies (4 cm Ø). Place on a baking tray lined with baking paper and bake in the preheated oven (electric range: 200°C/ gas: level 3) for 8-10 minutes and let cool off. Drain pineapple and mandarins on a sieve. Cut the pineapple into pieces, except for 1 ring for decoration. Set aside a few slices of mandarin oranges for decoration. Mix quark and lemon juice, whip 400 g cream until stiff. When the milk begins to set, stir in the quark and cream. Finally, fold in the fruit. Place a springform pan or cake rim (if using a springform pan rim, line the rim with parchment paper) around the shortcrust pastry base and fill in the quark mixture.
Cut the pineapple into pieces, except for 1 ring for decoration. Set aside a few slices of mandarin oranges for decoration. Mix quark and lemon juice, whip 400 g cream until stiff. When the milk begins to set, stir in the quark and cream. Finally, fold in the fruit. Place a springform pan or cake rim (if using a springform pan rim, line the rim with parchment paper) around the shortcrust pastry base and fill in the quark mixture. Smooth the filling and put in a cool place for at least 6 hours, preferably overnight. Remove the cake from the edge with a sharp knife. Whip the rest of the cream until stiff and fill into a piping bag with star-shaped spout. Decorate the cake with 8 cream tuffs and 8 cookies in alternation. Decorate with remaining fruit
Smooth the filling and put in a cool place for at least 6 hours, preferably overnight. Remove the cake from the edge with a sharp knife. Whip the rest of the cream until stiff and fill into a piping bag with star-shaped spout. Decorate the cake with 8 cream tuffs and 8 cookies in alternation. Decorate with remaining fruit
Freezing the cake: leave the biscuit decoration off and freeze the cake for 1-2 hours. Only then pack the cake. After defrosting (at room temperature about 5 hours) decorate the cake with the cookies, which can be kept in tins