The secret to a delicious minestrone is to use a variety of good vegetables and allow the ingredients to simmer for at least an hour. Cauliflower, turnips, carrots, and other fresh vegetables may be used in place of or in addition to the ingredients called for in this recipe.
FOR THE SOUP:
1 oz. dried porcini mushrooms
1⁄4 lb. swiss chard
1⁄4 lb. spinach
2 small zucchini, diced
2 medium white potatoes, peeled and diced
2 Japanese eggplants, peeled and diced
2 tbsp. extra-virgin olive oil
2 cups tubetti pasta
2 cups cooked white beans
Freshly ground black pepper
FOR THE PESTO:
2 tbsp. pine nuts
1⁄2 tsp. salt
2 cloves garlic, peeled and chopped
2 cups packed basil leaves
1⁄2 cup extra-virgin olive oil
2 tbsp. grated parmigiano-reggiano
1. For the soup: Soak mushrooms in 2 cups warm water until soft, about 20 minutes. Remove mushrooms, rinse, chop, and set aside. Pour mushroom water through a coffee filter and reserve. Wash chard and spinach in several changes of cold water. Trim and discard stalks from chard and stems from spinach. Chop leaves.
2. Bring mushroom water and 6 cups salted water to a boil in a large pot. Add mushrooms, chard, spinach, zucchini, potatoes, eggplant, and olive oil. Reduce heat to low and simmer, uncovered, for 1 hour.
3. For the pesto: Pulse pine nuts and salt in a food processor until finely ground. Add garlic and basil, and drizzle in olive oil. Add parmigiano-reggiano and process into a smooth paste.
4. Add pasta to soup. Cook pasta for about 10 minutes; add beans and cook 5 minutes longer. Stir in 2 tbsp. pesto, reserving the rest for another use, and season with salt and pepper. Serve hot or, in the Genoese tradition, at room temperature. If desired, sprinkle with additional grated parmigiano-reggiano.