Divide each head of chicory in half; grease the pan with a little oil and cook, over low heat, the radicchio, turning it gently so as not to break it; place it in a well-stretched container.
Preparation of the “saor”: slice the onion very thinly and let it dry, over low heat in oil (time about 15 minutes), checking that it does not take color (it should not fry) add the vinegar, raisins, pine nuts, salt, pepper and cook another 5 minutes. Pour the 'saor' over the chicory, close the container and let it rest at least 24 hours before serving it. It is also good as a side dish.