To start, tenderize the octopus by placing it in a resealable plastic bag, and then gently massage and toss it for about 10 times.

This method is more humane and achieves the desired tenderness without the need to throw it forcefully into the sink.

For the cooking liquid: In a large pot, bring the 12 cups of water to a boil over high heat.

Submerge the octopus in the boiling water, then remove it immediately.

Repeat this process twice, and then transfer the octopus to a platter.

Add the bay leaf, onion, peppercorns, parsley, and salt to the pot, and bring it to a boil again over high heat.

Return the octopus to the pot, reduce the heat to low, cover, and let it simmer until tender.

The cooking time will vary, taking approximately 1¾ to 3 hours, depending on the size of the octopus.

Once done, drain the octopus, discard the bay leaf, and let it cool.

Scrape off any loose skin, and cut the body and tentacles into bite-size pieces.

For the dressing: In a medium bowl, combine all the dressing ingredients.

Add the octopus and let it marinate in the refrigerator overnight.

Serve the marinated octopus cold or at room temperature, garnished with fresh herbs or a drizzle of olive oil for a delightful modern twist on this Galician classic.