Wash the strawberries, drain in a sieve, clean and halve. Mix strawberries, vanilla sugar and sugar in a bowl, let it stand for about 1 hour. Stir carefully several times.
Wash the lemon balm and shake dry. Pluck the leaves from the stalks. Add rhubarb juice and wine, fill up with Prosecco. Add lemon balm. Pour into glasses and serve immediately
Waiting time approx. 1 hour