1. Heat the olive oil in a large pan over a medium heat, then add the pancetta and gently fry for 1 min. Add the onion, celery, carrot, crushed garlic and sage leaves, then fry for another 2 mins until softened. Stir in the diluted tomato purée and the chickpeas, including the water from the can, then add the vegetable stock and some salt. Bring to the boil, then lower the heat and cover the pan with a lid. Leave to simmer for 10 mins.
2. Turn the heat back up and add the broken spaghetti. Leave on a high heat for 10 mins or until the pasta is cooked, then remove and stir in the parmesan, before placing the lid back on and leaving the mixture to rest for 3 mins, or until the parmesan has melted. In the meantime, toast the bread, then rub each slice with the remaining garlic clove and drizzle over some olive oil. To serve, top each portion of pasta with a little fresh red onion and parsley, plus a generous drizzle of the olive oil. Season to taste.