Soak the gelatine and squeeze it out. Yogurt, lemon juice, grated lemon zest, vanilla sugar and pulp of the vanilla pod as well as 4 tablespoon. Mix the icing sugar together. Add the gelatin and mix well.
Fold in the whipped cream.
Rinse 4 cups with cold water and pour in the cream evenly. Cover and chill for at least 4 hours.
Leave some raspberries as a garnish, the rest with 2 tablespoon. Puree the powdered sugar and pass through a fine sieve.
Carefully turn the mousse out onto a plate, garnish with raspberry purée and raspberries.