Fill a pot with 1 gal of water, add lemon juice, white wine, black peppercorns, celery stalk, yellow onion and enough salt to make it taste like the sea.
Bring your poaching liquid to a simmer and add your octopus to the pot slowly.
Using tongs and holding the octopus by the head, dunk the octopus’ body into the simmering water 3 times, leaving it submerged for about 5 seconds each time. This is called “scaring” the octopus, because the tentacles will curl up as you plunge the octopus into the water. Cook for 30-45 mins or until fork tender.
Once the octopus is cooked, it should be chilled thoroughly before dicing. After your octopus is chilled, slice off the head and discard it. If the beak is intact, push it out and discard as well.
Remove each tentacle individually and large dice them. Keep the diced meat chilled until you combine the campechana.