In a medium saucepan, combine 300 g of frozen raspberries with 90 g of granulated sugar. Over medium heat, simmer for 5-7 minutes until softened and juicy. Strain through a fine sieve to remove seeds, collecting juice for later use.

In a large bowl, blend 200 g of cream cheese, 250 g of mascarpone, and 8 g of vanilla sugar using an electric mixer until smooth. Gradually add 400 ml of whipping cream, mixing until soft peaks form.

Line a springform pan with parchment paper. Dip 300 g of tea biscuits into 150 ml of milk and layer half in the pan. Spread half of the cheesecake filling over, followed by half of the raspberry juice. Repeat layers, finishing with the remaining filling.

In a small saucepan, heat 75 ml of whipping cream until warm. Stir in 125 g of chopped white chocolate until melted and smooth. Cool slightly before pouring over the cheesecake.

Cover the springform pan with plastic wrap and refrigerate overnight to set.

Carefully remove the cheesecake from the springform pan, slice, garnish with fresh raspberries and mint leaves, and serve chilled.