Stir yogurt, crème fraîche, sugar (1) and port wine or sherry, if desired. Refrigerate.
Clean the strawberries and cut into slices. Marinate briefly with the sugar (2).
Coarsely chop the pistachios.
Arrange the yogurt soup in deep plates. Decoratively form the strawberries on top. Garnish with the pistachios and lemon balm.
Tip: The higher the fat content of the yogurt, the more aromatic and creamy the result!