Rinse the octopus under running water and cut into small pieces.
Place them in a non stick frying pan and cook, without adding any water, for about 20 minutes, with lid on. We cook it this way in order to tenderize. Don't be afraid, it will not stick to the pan, as it will boil in its own liquids.
Remove the pan from the heat and strain the octopus pieces.
In a hot pot stir to sauté the onions, until caramelized. Pour in the olive oil and when hot, reduce fire to low and stir in octopus to sauté pieces for about 4-5 minutes.
Deglaze with the wine and allow reducing.
Then add to the pot the tomatoes, tomato paste diluted in water, carrots, parsley, salt and pepper to taste. Raise fire on high and bring to a boil.
After boiling has occurred, again reduce fire to low and simmer for about 30-35 minutes, until the octopus pieces are tender and the sauce has thickened.
Remove the pot from the heat and serve garnished with parsley leaves.