Place the octopus is a vacuum bag and seal the bag, then place the bag in water and cooking using the sous vide method, at 135°F for 2.5 to 3 hours.
In a mixing bowl mix the juice from 2 fresh oranges, 2 tablespoon oregano, 1 minced serrano pepper and the olive oil set to the side we will use this as a brush for the octopus when we grill it.
Remove the octopus from the water bath then remove it from the bag. Dry it off at this point then slice of the tentacles and start to grill them while grilling brush with the mix we made above. Grill the octopus till you start to get a slight char then remove from the grill and slice into bite-size pieces.
Add the parsley, cilantro, garlic, 1 of the serrano peppers, 3 tablespoons diced onion, red vinegar, 3 tablespoon lime juice and 1 tablespoon oregano to the blender and blend. Set this to the side we will use it to dress the tacos at the end.
In a small bowl mix shaved red cabbage, shredded carrots, and shaved radish. Set aside we will use this to garnish the tacos.
Peel the Jicama, then slice the jicama on the slicer so it is thin enough that it will bend and not break after it is slice wrap them tight so they will not dry out.
Start by grilling the Jicama tortilla then top with the mix of cabbage we made above place the sliced octopus and dress with the chimichurri sauce and garnish with fresh lime
If you do not have a Sous-Vide machine handy, you can place your octopus in a plastic bag and cook it in a large pot of water at 135°F for 2.5 to 3 hours. You can maintain a consistent temperature with the help of a digital thermometer and adjusting your burners as necessary.