This light, creamy soup makes a simple, elegant lunch or first course for dinner; it”s topped with bright green pistou (like pesto, but without the pine nuts). Some pistou versions add finely grated mimolette, gruyere, or other hard cheese—I’m keeping this one vegan. I also added chives for a fresh, peppery bite. The word “pistou” means pounded, and the classic sauce is made in a mortar and pestle, which doesn’t work well with chives. I used a small food processor on the lowest possible setting, but you can try your hand at pounding. Use a blend of zucchini, yellow crookneck and delicata squash, or whatever’s available in your garden or at the market, and serve it hot or chilled. 

Serves 4 to 6

2 tablespoons olive oil
1 small Vidalia or other sweet onion (substitute yellow onion)
2 thin-skinned potatoes, peeled and chopped  (1 1/2 cups)
3 summer squash, zucchini or any combination, chopped (about 4 cups)
4 cups vegetable stock
Pistou:
2 garlic cloves, crushed
1 1/2 cup packed basil leaves
1 cup chopped chives
1/4 teaspoon salt
1/3 cup olive oil
Fresh chives and parsley for garnish

1. Heat olive oil in a large pot over medium heat and cook onion for 3 to 5 minutes, until just tender. Stir in potato and squash, and toss to coat with oil.
2. Add 3 cups of the stock, bring to a boil, reduce heat and cook, partly covered, until potatoes are tender, about 10 minutes.
3. While soup is cooking, make pistou: combine garlic, basil, chives and salt in a small food processor, and process on the lowest setting until ingredients are finely chopped. With machine running, slowly add oil until it’s completely incorporated, scraping down sides as needed; process until well blended. Transfer to a small dish and set aside.
4. When soup has finished cooking, add to the food processor and puree in batches, until smooth and creamy. Add additional stock as needed to reach desired consistency.
5. To serve, divide soup between 4 to 6 bowls. Stir a spoonful of pistou into soup, and garnish with fresh chives and parsley. Serve immediately.