Chilled Zucchini-Mint Soup

• 1 tbsp. butter
• 1 cup diced onion
• 4 cups sliced zucchini
• 1 cup chicken or vegetable broth, or wter
• 1/3 cup chopped fresh mint leaves, plus sprigs for garnish
• ½ tsp. salt
• 2 ½ cups buttermilk

1. In a medium saucepan, melt the butter over medium-high heat. Add the onion and sauté until softened, 3 to 5 minutes.
2. Add the zucchini and broth. Cover and simmer for 10 to 15 minutes, until the zucchini is soft.
3. Remove from the heat and cool slightly. Process the soup in a blender or food processor until smooth. Add the chopped mint and salt; process just to mix.
4. Pour the soup into a large bowl; stir in the buttermilk. Chill the soup, covered, in the refrigerator for several hours.
5. Serve chilled, garnished with springs of mint.

from The Classic Zucchini Book by Nancy Ralston, Marynor Jordan and Andrea Chesman