Slightly adapted from Matthew Goodman’s Jewish Food: The World at Table
1 teaspoon vanilla extract
Up to 1/2 cup sugar
1 cinnamon stick
1/4 teaspoon salt
Juice and zest of one lemon
1 pound plums, pitted and chopped
7 cups water
2 pounds peaches, pitted and chopped
1/2 cup sour cream (optional)
Put fruit, water, and salt in a soup pot and bring to boil. Add lemon juice, zest, cinnamon stick, vanilla, and 1/4 cup sugar. Lower heat and simmer for 15 minutes, stirring occasionally. Remove cinnamon stick.
Puree the soup in the pot with a hand (immersion) blender, or in batches in a standard upright blender. Transfer to a bowl and stir in additional sugar, to taste. Refrigerate overnight and serve with sour cream.