Separate the eggs for the sponge cake. Beat the egg whites with 1 pinch of salt until stiff, adding 150 g sugar. Carefully stir in the egg yolks. Mix flour, starch, baking powder and 110 g ground almonds and fold into the egg mixture. Line the bottom of a springform pan (26 cm Ø) with baking paper. Smooth the mixture in it. Bake in a hot oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer) for about 30 minutes. Let it cool down.
For the compote 500 g plums wash, halve, stone and dice. Caramelise 100 g sugar in a pot. Deglaze with plum juice. Simmer until the sugar is dissolved. Add plums and rum, bring to the boil and simmer for 2-3 minutes. Stir pudding powder with a little water until smooth. Bind the compote with it, bring to the boil again. Let cool off.
Remove the sponge cake from the tin and remove the baking paper. Cut the sponge twice horizontally. Cover the lower sponge cake base with a cake ring and sprinkle with 3 tbsp. ground almonds. Set aside 3 tbsp. compote. Spread the rest of the compote on the sponge cake base. Chill sponge cake with compote for about 45 minutes.
For the cream, soak gelatine in cold water. Mix the quark, yoghurt and 100 g sugar. Squeeze the gelatine, dissolve at low heat. First stir 2-3 tablespoons of cream into the gelatine, then stir everything into the rest of the cream. Whip cream until stiff, fold in 2 portions. Puree the stewed compote that has been set aside, pass through a sieve and fold into the cream.
1⁄4 Spread the cream on the compote. Place the middle sponge cake base on top and spread 1⁄4 cream again. Place the upper sponge cake base as a lid on top. Remove the cake from the ring and spread the remaining cream all around with 2⁄3. Spray the rest of the cream tuffs onto the cake. Chill the cake for about 2 hours.
Roast the flaked almonds in a pan without fat, let them cool down. Wash 2-3 plums, halve, stone and cut into slices. Decorate cream cake with almonds and plums.