Cut the jackfruit into small pieces, remove the shell, seeds and yellow pulp. Rinse it thoroughly and cook in a frying pan with water over medium heat with a little bit of salt until boiling, and then let it cook for another 20 minutes.
Squeeze the oranges and blend 1 cup with achiote paste, 1/2 cup of vinegar, Mexican oregano, pepper, garlic cloves, half onion and salt to taste.
Strain the jackfruit to remove the excess water and bathe it with the achiote marinade, let it sit for a few minutes.
Meanwhile, in a bowl, add the onion sliced, habanero chopped, orange juice, vinegar and salt, cover-up and place in the fridge whilst cooking the jackfruit.
Pour the marinated jackfruit in a saucepan over low heat and cover, including the marinade, and cook for 1 hour, then shred the jackfruit with two forks and cook for 15 more minutes so that the flavors are well incorporated.
Re-heat the corn tortillas and fill them with the jackfruit adding the pickled onions and habanero on top.