Bring the sock to a boil or simmer together the water, salt, pepper, onion, garlic, carrot, parsley, Bay leaves, vinegar, and wine for about 10 minutes.
Add the octopus and simmer until tender, one hour or more. (Poke it with a sharp, thin-bladed knife; When the knife enters fairly easily, the octopus is ready to make sure to cut a piece off and taste it; it should be pleasantly chewy).
Turn off the heat and let the octopus cool in the water for 10 minutes.
Strain and reserve the stock for another use.
Cut the octopus into bite size pieces.
In a small saucepan over medium-low heat, heat the olive oil and garlic until the garlic sizzles and colors slightly.
Turn off the heat and cool; Mix in the paprika and Sherry vinegar, along with some salt and pepper.
Pour over the octopus and mix well. Refrigerate for at least one hour, or overnight.
Garnish with the mince parsley before serving.