Mix jelly powder with 1/4 l water and allow to soak for approx. 5 minutes. Then add sparkling wine, lemon juice and sugar. Heat while stirring (do not boil) until everything is dissolved. Chill the lemon dish, but do not let it set. Then whip the cream and vanilla sugar until stiff. Fold with the sour cream under the slightly gelled lemon dish. Pour into a bowl and let it set in the refrigerator.
Tip:
Before serving, decorate with mint, cocoa powder or chocolate flakes as desired.