Defrost berries at room temperature. Lightly oil the bottom of a springform pan (20 cm Ø). Melt the butter in a pot. Coarsely chop the almonds and roast them in a coated pan without fat until golden brown.
Coarsely crumble the biscuits. Mix both well with the liquid butter. Press the mixture evenly into the mould as a base and chill for approx. 30 minutes.
Soak 5 sheets and 1 sheet of gelatine separately in cold water. Wash the lemon hot, dry it and rub the peel thinly. Halve the lemon and squeeze it. Whip cream until stiff and chill.
Mix cream cheese, yoghurt, 150 g sugar, vanilla sugar, lemon peel and 3 tbsp lemon juice with the whisks of the mixer until smooth. Squeeze 5 sheets of gelatine, dissolve at very low heat (important!) and remove from the heat.
Stir in 2 tablespoons of cream cheese cream, then stir into the remaining cream. Fold in the cream immediately. Spread the cream on the crumb base and chill for approx. 30 minutes.
Finely puree blueberries and 2 tablespoons of sugar with a hand blender. Squeeze out 1 sheet of gelatine, dissolve at very low heat and remove from the stove. First stir in 1 tbsp. blueberry puree. Then stir into the remaining puree.
Pour the puree onto the cream cheese and distribute evenly. Cover the cake and chill for at least 4 hours.