Defrost berries at room temperature. In the meantime, stir cream cheese, 125 g sugar, vanillin sugar, lemon peel with the whisk of the hand mixer until creamy. Add flour, then stir in eggs and egg yolks one by one. Stir in sour cream. Halve the dough. Finely chop 1/3 of the berries with the hand blender and stir into one half of the dough.
Fill dough alternately into a greased box form (26 x 11 cm). Pull spirally through the dough with a fork. Bake in the preheated oven (electric cooker: 150 °C/ convection oven: 125 °C/ gas: level 1) for approx. 1 1/2 hours. Take the finished cake out of the oven and spread chocolate-coated biscuits on top of it. Let the cake cool down well. In the meantime mix starch and 50 g sugar. Stir with 3 tablespoons of nectar until smooth. Boil up the rest of the nectar. Add the starch while stirring, bring to the boil. Fold in remaining berries. Roast almonds in a pan without fat for about 3 minutes.
In the meantime mix starch and 50 g sugar. Stir with 3 tablespoons of nectar until smooth. Boil up the rest of the nectar. Add the starch while stirring, bring to the boil. Fold in remaining berries. Roast almonds in a pan without fat for about 3 minutes. Heat the jam, pass through a sieve and coat the cake with it. Sprinkle the cheesecake with almonds, cut into pieces and serve with the berry groats