Heat a couple of tablespoons EVOO, two turns of the pan, over medium-high heat in a large soup pot or Dutch oven. Add the pancetta, if using, and cook until lightly browned. Add the sliced fennel, cabbage, onion and garlic; season with salt and pepper. Throw in the Parmigiano Reggiano rind and bay leaf, cover the pot and sweat the fennel and cabbage, stirring occasionally, for 5 minutes. Add the chicken or vegetable stock and the beans and bring to boil. Stir in the fusilli and cook until just about al dente. Stir in the peas, turn off the heat and let stand for 5 minutes. Discard the cheese rind and bay leaf. Season with salt and pepper, to taste.
Meanwhile, using a food processor, pulse the packed herbs, fennel fronds, pine nuts, lemon juice, grated cheese, remaining 3-4 tablespoons EVOO and salt and pepper into a pesto.
Serve the soup in shallow bowls with spoonfuls of the pesto for mixing in. Pass the hunk of cheese for grating at the table