For the lemon balm sorbet in a jar, first wash the lemon balm, blanch in boiling water for about 30 seconds and then rinse in ice water. Puree dripping wet in a blender until fine and set aside.
Bring the sugar to a boil with 100 ml of water and cool to room temperature. Mix with the lemon juice, sparkling wine and the pureed lemon balm. Freeze in the ice cream maker according to manufacturer’s instructions to make sorbet and serve in glasses. Garnish the lemon balm sorbet in the glass with fresh lemon balm or mint, if desired.