Line the bottom of a springform pan (26 cm Ø) with baking paper. Separate the eggs. Beat the egg whites and 3 tbsp. cold water until stiff, adding 75 g sugar and 1 packet of vanilla sugar. Beat the egg yolks separately into the mixture. Sift flour, starch and baking powder into the mixture and fold in. Spread into the mould. In a preheated oven (electric cooker: 175 °C/recirculating air: 150 °C/gas: level 2). Bake for 25-30 minutes. Cooling down
Drain the apricots well. Cut the sponge cake 1x horizontally so that the lower base is a little thicker. Place a cake ring (approx. 7.5 cm high) around the bottom base
Soak 1 1 sheet of gelatine in cold water. Mix yoghurt, 100 g sugar, 1 packet of vanillin sugar and lemon zest. Squeeze the gelatine, dissolve over a mild heat. Stir in liqueur and 3 tbsp. yoghurt by the spoonful. Stir into the remaining yoghurt. Beat 250 g cream until stiff, fold into the cream. Spread approx. 1/4 of the cream on the lower base. Cover with half the apricots. Pour the rest of the cream on top, except for 4-5 tbsp (do not chill). Chill for about 15 minutes.
Soak 3 sheets of gelatine in cold water. Puree half of the remaining apricots and 25 g sugar. Squeeze the gelatine, dissolve over a mild heat. Stir in the puree by the spoonful, then the rest of the yoghurt cream. Spread on the cake. Place the second cake layer on top. Chill for at least 7 hours, preferably overnight
Roast the almonds and let them cool down. Whip 350-400 g cream and 1 vanillin sugar until stiff. Spread the cake with 2/3 cream. Sprinkle cake edge with almonds and chopped pistachios. Cut the rest of the apricots into slices and place them on the edge. Decorate the cake with the rest of the cream and ground pistachios