Traditionally, this Yucatán-style pork is cooked all day in a pit, but a pressure cooker gets it on the table much quicker. Cooking the pork wrapped in banana leaves is optional but adds an authentic grassy note.
To prepare pork: Whisk spice blend, 2 1/2 tablespoons vinegar, orange juice, lime juice, garlic and 1 1/2 teaspoons salt in a large bowl. Add pork and stir to coat.
If using banana leaves, rinse off any white residue and trim any hard, brown edges. Place one leaf so it covers the bottom of the inner pot of a 6-qt. electric pressure cooker. (Or see Oven Variation.) Arrange the pork in a single layer and drizzle with any juices from the bowl. Pour 1 cup water around the pork. Cover with the other banana leaf. (If not using banana leaves, proceed without them, arranging the pork and adding the water.)
Lock the lid and cook at high pressure for 45 minutes.
Meanwhile, to prepare pickled onion & peppers: Place onion in a small, deep heatproof bowl. Cover with 2 cups water and let soak for 10 minutes. Drain well, then return to the bowl. Add peppers.
Combine the remaining 1/4 cup water, vinegar, cloves (or allspice), oregano, peppercorns and salt in a small saucepan. Bring to a lively simmer over high heat, then pour over the vegetables. Set aside, stirring occasionally.
Let the cooker pressure release naturally for 15 minutes. Carefully release residual pressure manually, unlock and remove the lid. Use tongs to remove the banana leaves.
Transfer the pork to a serving platter and shred with 2 forks. Loosely cover with a banana leaf or foil to keep warm. Pour the cooking liquid into a measuring cup and set aside for 10 minutes. Skim off any fat. Return the liquid to the pot, set the cooker to Saute on high and bring to a boil. Cook until reduced by half, 5 to 7 minutes. Mix the liquid into the pork.
Drain the vegetables and remove the whole spices. Serve the pork and vegetables in tortillas with crumbled cotija and lime wedges, if desired.
Annatto Spice Blend