Preheat the oven to 180°C (350°F). Combine ground biscuits and ground pistachio in a mixing bowl. Melt the butter and mix it in, then press into the bottom of an 18cm round pan. Bake for approximately 12.5 minutes until golden brown and cool completely.

Soak gelatin leaves in cold water for 5–10 minutes. Heat milk and half the sugar in a saucepan until simmering. Whisk remaining sugar with egg yolks until pale, then gradually whisk in hot milk. Cook until thickened, then stir in bloomed gelatin. Fold in raspberry puree and whipped cream, then pour over cooled cake base.

Gently heat milk with pistachio paste until simmering. Whisk egg yolks and sugar until creamy. Combine hot milk with yolks, return to saucepan, and cook until thickened. Stir in bloomed gelatin and let cool. Fold in whipped cream, pour onto set raspberry bavarois, and refrigerate overnight.

Once set, carefully remove from the pan. Optionally, sprinkle ground pistachio and decorate with fresh raspberries. Slice and serve chilled.