Put the carrot, 1 spoonful of parsley, the whole peeled onion and 2 stalks of celery in pieces, on the stove in a saucepan full of lightly salted water. When the water comes to the boil, take the octopus by the head, dip it in the saucepan for a moment and then pull it out again – the tentacles will curl up. Plunge it back in, put the lid on and boil for roughly 40 minutes, until it’s tender. Turn of the heat and leave the octopus to cool down in its water. Now take it out and put it on a chopping board; cut it into pieces (not too small) and put them in a salad bowl.
Peel the potatoes and boil them whole in the water in which you cooked the octopus. Strain the potatoes that, having been cooked in the octopus’s water, will have turned slightly pink, and cut them into cubes. Put them in the bowl with the octopus, together with the remaining stalk of celery, chopped into small pieces, a spoonful of coarsely chopped parsley and the olives. In a small bowl, prepare an emulsion by mixing the oil and juice of the lemons together with a fork, then pour it over the octopus. Stir everything together well, season with salt if necessary and, after leaving the salad to rest for a couple of hours, serve it sprinkled with the remaining chopped parsley – “someone”, however, won’t be able to resist and will taste it straight away!