1. Peel the onions and garlic. Peel the carrot. Chop the celery, carrot, onions, and garlic. In a saucepan, heat the extra virgin olive oil and cook all the vegetables, stirring, for 5 minutes. Finely chop the tofu and add it to the vegetables. Cook for a few minutes. Cover the saucepan and continue cooking, over low heat, for 5 to 6 minutes.
2. Add the vegetable broth, a pinch of salt, a pinch of freshly ground pepper, and the tomato puree. Cook for 20 minutes over medium heat, until the sauce has reduced a bit. Add the chopped basil leaves. Add salt to taste.
3. In a large quantity of boiling salted water, cook the spaghettonis cut into 3 pieces, until they are al dente. Drain and add them to the sauce. Mix well. Add the grated caciocavallo cheese. Mix again and serve.