2 pounds ripe purple plums, washed, cut in half, and pitted
1 6-inch thin strip of orange zest
1½ cups orange juice
1/4 teaspoon cinnamon
1/2 teaspoon cardamom
1/8 teaspoon ground cloves
1/2 cup honey
1/2 cup plain yogurt
2 teaspoons balsamic vinegar
Garnish: Spoonsful of yogurt swirled in each serving
Mix plums, orange zest, orange juice, cinnamon, cardamom, cloves, and honey in a saucepan. Bring to a boil, then reduce heat, cover, and simmer for about 30 minutes, until the fruit is very soft.
Purée the entire contents in a blender, skins and all. Stir in the yogurt. If you plan to serve it cold, chill in the refrigerator for several hours.
When ready to serve, add more orange juice, to achieve your preferred consistency. Stir in the balsamic vinegar, then ladle into small bowls. Swirl a spoonful of yogurt into each portion as a garnish.
Perfect soup to go with lamb.