How to make
Pour 2 liters of water into a large pot. Add the whole onion, carrot, stalk of celery, pepper grains and bay leaves. When the water boils, submerge only the tentacles of the octopus, by holding it by the body.
Repeat 2 more times. That way the tentacles will curl up and sit nicely in the salad. Put the octopus in the water and boil it for about 35-40 minutes.
Before taking it out, poke it with a fork to make sure it's fully cooked. Cut the cooled octopus into small pieces.
Peel and boil the potatoes. Cut them into small pieces. Add the octopus, season with a pinch of black pepper, finely chopped parsley and finely chopped red onion. Season with balsamic vinegar and lemon juice. Homogenize all of the products well.
Pour the potato salad into a suitable plate, garnish it with the curled octopus tentacles and serve it.