Summer Roasted Vegetable Soup with Pesto
Roasting the vegetables in the oven before pureeing them adds a depth of flavor to this summery soup, as does a dollop of freshly made pesto. You can substitute vegetable stock for the chicken stock to transform it into a vegetarian dish.
For the soup:
- 2 leeks, white and pale green parts, finely chopped
- 4 carrots, peeled and cut into 2-inch (5-cm) pieces
- 2 zucchini, cut into 2-inch (5-cm) pieces
- 2 Asian eggplant, cut into 2-inch (5-cm) pieces
- 2 large tomatoes, quartered
- 2 potatoes (about 10 oz./315 g), peeled and cut into 2-inch (5-cm) pieces
- 4 1/2 cups (36 fl. oz./1.1 l) chicken broth, plus more as needed
- 2 Tbs. olive oil
- Salt and freshly ground pepper
- 2 Tbs. finely chopped fresh basil
- 2 Tbs. fresh lemon juice
For the pesto:
- 1/3 cup (2 oz./60 g) pine nuts
- 3 garlic cloves
- 2 cups (2 oz./60 g) packed fresh basil leaves
- 1/2 cup (4 fl. oz./125 ml) extra-virgin olive oil
- 1/2 cup (2 oz./60 g) grated Parmesan cheese
- Kosher salt and freshly ground pepper
Preheat an oven to 425°F (220°C).
In a large, heavy roasting pan, combine the leeks, carrots, zucchini, eggplant, tomatoes and potatoes. Add 1/2 cup (4 fl. oz./125 ml) of the broth and the oil, season with salt and pepper, and mix until the vegetables are well coated. Roast, turning once, until the vegetables are softened, about 40 minutes.
While the vegetables are roasting, make the pesto: In a blender or food processor, combine the pine nuts and garlic and process until finely chopped. Add the basil leaves and process until coarsely chopped. With the motor running, add the olive oil in a steady stream and process until a thick green sauce forms. Add the Parmesan, process to combine and season to taste with salt and pepper.
Remove from the vegetables from the oven and let cool slightly. Working in batches, puree the vegetables with 1/2 cup (4 fl. oz./125 ml) of the broth. Transfer to a large saucepan and stir in the remaining 3 1/2 cups (28 fl. oz./875 ml) broth, the basil and lemon juice. If needed, add more broth to achieve the desired consistency. Cook over low heat for 3 minutes to blend the flavors. Season with salt and pepper and ladle into individual bowls. Add a dollop of the pesto to each bowl and serve immediately. Serves 4 to 6.
Adapted from Williams-Sonoma Soup of the Day, by Kate McMillan (Weldon Owen, 2011).