Prep the Plums: Bring a medium saucepan of water to a boil. Blanch the plums in batches for 10 seconds each.
Remove with a slotted spoon.
Once cool enough to handle, peel the plums. 2. Create the Flavor Base: Place the plum skins in the now-empty saucepan with the red wine and 1/2 cup (480 ml) of water.
Bring to a boil and cook for 5 minutes.
Strain the liquid through a fine-mesh sieve, pressing on the skins to extract all the flavorful liquid.
Discard the skins. 3.
Simmer the Soup: Cut the peeled plums into bite-sized pieces, discarding the pits.
Add the plum pieces to the saucepan with the strained wine mixture.
Stir in the ground coriander, allspice, salt, and honey.
Bring to a boil, then reduce the heat and simmer for 10 minutes until the plums are tender. 4.
Blend and Chill: Carefully transfer the hot plum mixture to a blender.
Add the heavy cream and blend until completely smooth.
Pour the soup into a large bowl or container and chill in the refrigerator for at least 1. 5 hours, or until very cold. 5.
Serve: Just before serving, whisk the sour cream into the chilled soup until it's smooth and fully incorporated. Ladle into bowls or cups and garnish with a fresh sprig of mint.
