Defrost blueberries at room temperature. Lightly coat a springform pan (20 cm Ø) at the bottom with oil. For the bottom melt butter and let it cool down a little. Put the butter biscuits in a freezer bag and close it.
Roll over with a cake roll until the biscuits are finely crumbled. Knead the crumbs and butter well. Pour the crumb mixture into the tin and press to a firm base. Chill for about 30 minutes.
Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Soak gelatine in cold water. Mix blueberries, mascarpone and sugar well with a tablespoon or dough scraper.
Stir in yoghurt and lime juice. Whip 250 g cream until stiff. Squeeze the gelatine. Dissolve in a small pot at very low heat while stirring. Stir about 2 tbsp. of the blueberry cream into the gelatine.
Then stir everything into the rest of the cream. Fold in the whipped cream. Spread the cream on the base and smooth it down. Chill for at least 4 hours.
Carefully spread almonds on a baking tray lined with baking paper - they must not break. Roast in a hot oven for about 5 minutes until golden brown. Take them out and let them cool down. Whip 150 g cream until stiff.
Remove the cake from the tin and spread with the cream. Decorate with raspberries and whole almond flakes. Keep cold until serving.