Cold Zucchini Soup

6 medium-large zucchini, cut into chunks
1 large onion
1 teaspoon curry powder
4 cups vegetable broth
1 ½ cups buttermilk or yoghurt
1 teaspoon salt
pepper to taste

Combine zucchini, onion, broth, curry, and salt in a large soup pot. Bring to a boil and simmer for about 30 minutes or until zucchini is soft. Turn off heat and blend. Add the buttermilk or yogurt and season to taste. Refrigerate until cold.

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