Preheat the oven (electric cooker: 175 °C / circulating air: 150 °C / gas: level 2). Peel and coarsely grate apples. Mix with 2 tbsp. lemon juice. Grind the poppy seeds in a poppy seed mill or universal chopper
Beat the eggs, 6 tablespoons of water, sugar, vanillin sugar and 1 bag of "biscuit-apart for approx. 7 minutes until lightly frothy. Mix the poppy seeds, hazelnuts, grated apple and the contents of the remaining bag and fold into the egg mixture
Line the bottom of a springform pan (24 cm Ø) with baking paper. Fill in sponge cake mixture. Bake in a hot oven for 50-60 minutes. Remove from the tin immediately and let it cool down on a cake rack
Stir icing sugar and 3 tablespoons lemon juice until smooth. Cover the cake with the icing. Roast the almonds. Decorate cake with crème fraîche and almonds