In a large but shallow pan, heat the oil over medium-low heat. Add the onion and fennel and gently saute for about 15 minutes. Then add the remaining fresh vegetables and minced herbs. When the vegetables are tender, transfer to a large pot. Add vegetable broth and spaghetti. Bring to a boil, then lower the heat and simmer for about 10 minutes. Season to taste with salt and pepper.
Serve in big bowls with a dollop of fresh pesto in the middle, a sprinkling of chopped basil and chives, and pinch of shaved Parmesan.