Wash the berries and cut into bite-sized pieces if necessary.
Soak the gelatine in cold water. Dissolve the sugar and vanilla sugar in the hot water, then dissolve the squeezed out gelatine in the hot sugar water and then let it cool down a little. Add the sparkling wine and stir gently.
Put the berries in chilled glasses, fill up with the sparkling wine mixture and refrigerate the glasses for about 4 hours before serving.