Cut Pork: Remove any large pieces of fat. Slice the pork horizontally into long, ¼’’ thick pieces (you could see if your butcher would do this).
Soften Chiles: Remove seeds and veins from the dried chiles (wear gloves if desired). Add to a small saucepan cover with water. Bring to a boil and then simmer for 15 minutes, to soften the chiles.
Blend: Add chiles and ¼ cup of water from the pot (discard remaining water) to a high powdered blender. Add onion, garlic cloves, allspice, peppercorn, cloves, Mexican oregano, cumin, ginger, achiote powder, salt, apple cider vinegar, and juice. Blend until completely smooth.
Marinate: Add pork to a large bowl or ziplock bag and spread mixture all over pork, tossing to coat. Cover and refrigerate for several hours, or overnight.
Grill Pork: Remove pork from marinade and cook on a very hot grill for a few minutes on each side until just shy of 145 degrees F. Remove to a cutting board allow to rest.
Grill pineapple: Brush pineapple spears with olive oil and place on hot grill, cooking briefly on both sides. Remove and chop into pieces.
Assemble Tacos: Chop pork into small pieces for serving. Warm tortillas in a hot dry skillet or on the grill. Top tortillas with a spoonful of pork some pineapple, onion, cilantro and a squeeze of lime juice.
