Beat the sour cream, sugar and vanilla sugar for a long time with the mixer. Soak the gelatine in the water, squeeze it out, dissolve it in the slightly warmed rum and add it. Whip the sweet cream until stiff and fold in.
Either stir in the raspberries or distribute them on the dessert bowls and pour the cream on top (looks more appealing). Chill everything for several hours until the cream is set.