Pour the wine and water into a saucepan, add the sugar, cinnamon stick and lemon rind and juice.
Bring to the boil and simmer for 5 minutes.
Add the still frozen cherries and simmer for 5 minutes.
Discard the cinnamon stick, then ladle half the liquid and cherries into a blender or food processor.
Add the soured cream and then blend, in batches if needed, until smooth.
Return the blended liquid to the saucepan and mix well.
Chill the soup thoroughly, then ladle into shallow bowls so that the whole cherries can be seen and sprinkle with a little ground cinnamon to garnish. Serve with some cherries on stalks, if liked.
Notes / Tips / Wine Advice:
For peppered strawberry soup, make up the syrup as above with the wine, water, sugar and lemon rind and juice, adding ½ teaspoon crushed coloured peppercorns in place of the cinnamon. Simmer for 5 minutes then add 500 g (1 lb) sliced or halved strawberries depending on their size. Finish the soup as above.