Bring all ingredients but the octopus to a boil. Plunge the octopus into boiling liquid for a couple of times for the tentacles to curl. Then add the octopus to the simmering liquid and slowly cooked for 1 ½ hour.
For the Romesco Sauce:
In a blender, slowly mix all the ingredients adding the extra virgin oil as last until the sauce is emulsified and stable.
For the Navy Beans:
Drain the soaked beans. Combine the first set of ingredients in a 4qt pot. Simmer for about 1 ½ to 2 hours or until the beans are soft to the touch but still firm. (Note: add the salt after 45 minutes). Drain the beans and remove all the boiling aromatic vegetables. In a saucepan, sauté the vegetable brunoise (small diced) with the extra virgin olive oil at medium heat for 5 minutes. Add the rosemary and vinegar. Pour directly on the beans.
For the Plating:
In a very hot sauté pan with the olive oil or a griddle, char the Spanish octopus and the spring onions until obtaining the color desired. Plate individually or family style. Paint the bottom of the plate generously with the Romesco sauce. Place the Navy beans, spring onions and the charred pulpo. Place the grapefruit segment around the beans and the thinly sliced chorizo on top of the pulpo.