Marinade: Peel the pineapple and cut into 2cm slices. Take two of the slices and roughly dice. Set aside.
Grill or roast the tomato until slightly charred then remove from heat. Once cool enough to handle, peel the skin and remove the seeds.
Remove the stalks and seeds from the guajillo and ancho chilles. Add the dried chillies to a small saucepan of boiling water. Boil for 5 minutes until softened then drain.
In a blender or food processor, combine the reserved pineapple, tomato, softened chillies, chillies in adobo sauce, onion, garlic, orange juice, vinegar, cloves, cumin, oregano and salt. Blend until smooth.
Pork and Pineapple: Place the pork in a glass or ceramic dish. Pour the marinade over the pork ensuring that all sides of the pork are covered in the marinade. Cover with plastic wrap and place in the fridge to marinate for at least 4 hours, or overnight.
Preheat a ridged griddle pan to medium high heat. Cook the pineapple slices for 10 minutes, turning once, until caramelized and soft.
Preheat another griddle pan to medium high heat. Place the marinated pork on the hot pan and cook for 4 to 5 minutes, turning once halfway through. Remove the pork and rest on a chopping board.
To Serve: Roughly slice or dice the pork into small pieces against the grain of the meat. Cut the pineapple into small pieces discarding the core.
Serve the pork and pineapple with warm corn tortillas and a variety of accompaniments, including coriander, onion, salsa and lemon or lime wedges.