Line the bottom of a springform pan (26 cm Ø) with baking paper. Separate the eggs. Beat the egg whites, salt and 2 tbsp. cold water until stiff. Add 75 g sugar and 1 packet of vanilla sugar. Beat the egg yolks separately into the mixture. Sift the flour, starch and baking powder into it and fold in. Spread into the mould. Bake in the preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for 15-18 minutes. Let them cool down
Soak gelatine in cold water. Drain the pineapple well. Wash, dry and halve the lime. Peel 1 half with a julienne sharpener in fine strips and squeeze the juice. Mix soured milk, lime juice, 75 g sugar and 1 packet of vanilla sugar. Squeeze the gelatine and dissolve over a mild heat. Stir in 2 tbsp. soured milk, then stir into the remaining soured milk. Cool until it begins to gel
Cut through the bottom 1 x horizontally. Place the edge of the springform pan around the bottom base. Whip 100 g cream until stiff. Fold cream first, then pineapple, except for 3-4 pieces, into the soured milk. Spread on the lower cake base. Place the 2nd cake base on top. Chill for about 4 hours.
Remove mould edge. Whip 300 g cream until stiff. Fill 1/3 into a piping bag with star spout. Spread the rest of the cream on the cake. Press the lime strips onto the edge of the cake. Cut the rest of the pineapple smaller. Cut the 2nd half of the lime into thin slices and quarter them. Cake with cream tuffs, lime slices, cookies, lemon balm and the rest of pineapple