Line a springform pan (26 cm Ø) at the bottom with baking paper. Separate the eggs. Beat the egg whites and 1 pinch of salt until stiff, adding 50 g sugar and vanillin sugar. Fold in the egg yolks one by one. Sift flour and baking powder on top and fold in. Spread into the form and bake in the preheated oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2) for 20-25 minutes. Allow to cool down
Soak gelatine in cold water. Mix sour cream, yoghurt, 3 tablespoons lemon juice, lemon peel and 60 g sugar. Squeeze the gelatine and dissolve at low heat. Stir in 3 tbsp. cream and then stir into the remaining cream. Spread on the sponge cake base and refrigerate for about 3 hours
Carve peaches crosswise. Dip briefly in boiling water, then rinse with cold water. Peel off the skin. Cut peaches in half, stone them and cut them into wedges. Sprinkle with the rest of the lemon juice. Dab dry and place on the cream. Warm the jam slightly, pass through a sieve. Spread on the peaches. Chill the cake for about 2 hours