Defrost the raspberries and mash just under 500 g with a fork. Leave the rest to cool. Add vanilla sugar to the mashed berries form and stir until the sugar has dissolved.
Soak the gelatin in cold water and squeeze lightly.
Melt with very little liquid in a saucepan over mild heat.
Add the dissolved gelatin to the raspberry mixture form and semi-stiffen.
Whip the whipped cream and mix gently. Pour everything into a mold and set aside to cool.
Shortly before serving, decorate the mixture with the sweetened raspberries while they are still cool.