Clean the octopus thoroughly; spread salt on the tentacles to remove the excess dirt and rinse with running water. Cover with water and simmer with ½ onion, celery, leek, carrot, orange, wine, and bay leaf. After 30 minutes, when it’s almost tender, remove the tentacles and chop them into large pieces; save the cooking broth, vegetables removed. Chop the other half of the onion and braise with the garlic and tomatoes in corn oil. Add the rice, braise for a bit longer, and add the octopus. Cover with the broth and simmer until the rice is cooked through and the octopus is tender. Add the herbs and serve.