1.Process zucchini, pistachios, spinach, rocket, basil, onion and garlic in a blender or food processor until just smooth. Add well-shaken buttermilk and lemon juice, season to taste and process until very smooth then divide among chilled bowls and refrigerate to chill well (30 minutes).
2.Serve topped with zucchini flowers and zucchini slices, pistachios, rocket, basil, and a good drizzle of both buttermilk and extra-virgin olive oil.
