Preheat your oven to 180°C (350°F). To begin the marinade, bring a small pot of water to a boil and add the dried guajillo and ancho chillies. Boil for 5 minutes to soften the chillies. Drain and place the softened chillies in a blender along with the garlic, vinegar, pineapple juice, cumin, oregano, cinnamon, cloves, achiote paste, salt, and pepper. Blend until smooth.

In a large bowl, pour the marinade over the thinly sliced pork shoulder. Use your hands to ensure the marinade is evenly coating the meat. Let the pork marinate for at least 2 hours or overnight in the refrigerator for best results, allowing the flavors to penetrate deeply.

Heat a large oven-safe skillet or griddle over medium heat and add the olive oil. Sear the marinated pork slices in batches, cooking for 2-3 minutes on each side until they begin to brown. You don’t need to fully cook them at this stage, as they will finish in the oven.

Once all the pork slices have been seared, layer them in the same skillet or transfer them to a baking dish. Place a few pineapple slices between the layers of pork to add sweetness and moisture during roasting.

Cover the dish with foil and transfer it to the preheated oven. Roast the pork for 25-30 minutes until fully cooked and tender, allowing the pineapple flavour to permeate the meat.

While the pork is roasting, prepare the garnishes. Finely chop fresh cilantro and onions and slice the lime wedges for serving. Set these aside for topping the tacos.

Once the pork is done, remove it from the oven and allow it to rest for a few minutes. Slice the roasted pork into thin strips, ensuring to mix the pineapple into the meat for added flavour.

To serve, warm the corn tortillas either in a dry skillet or wrapped in foil in the oven. Fill each tortilla with a generous portion of sliced pork, top with cilantro, diced onion, and a squeeze of lime juice. Add a slice of fresh pineapple and your favourite salsa for extra brightness and spice.