Method

• 1.
  Dry octopus well with paper towel, then cut away the central beak. Place the olive oil in the pan over high heat until the oil just begins to smoke.
• 2.
  Holding the tentacles together in one hand, lower the octopus head into the pan and seal the flesh on one side. Lower tentacles in and swirl them around edges of pan, until everything is well submerged in oil. Cook for about 3 minutes. This will give the octopus an incredibly deep pink/burgundy hue. Turn the octopus and repeat the process on the other side. Reduce heat immediately to low and add oregano. Cover pan with a lid and simmer for 15-45 minutes. (Time will vary depending on the size of the octopus and thickness of the tentacles.)
• 3.
  Keep a close eye on the octopus: as the tentacles first begin to come away from the head, it's cooked. Set aside until cool enough to handle.
• 4.
  Meanwhile, to make the vinaigrette, combine lemon rind and juice and oil in a large bowl. Season with pepper.

• 5.
  Transfer octopus to a large chopping board. Pull tentacles away and slice on the diagonal into 2-3cm pieces, placing pieces into vinaigrette. Repeat with head. Garnish with basil and serve with garlic mayonnaise and oven-roasted tomatoes.