1. Cook the chiles in the vinegar, water, cumin, pepper, salt, and cloves over medium heat until they become very soft.
2. Pour the whole mixture (be careful or be burned) into the blender, add the garlic, and puree.
3. Heat the oil, add the blended mixture and simmer for fifteen minutes.
4. Cut the pork into small chunks, put it in a bowl, pour the marinade over the top, and let it sit covered overnight in the refrigerator.
5. Slowly grill the marinated meat in a splash of oil over low heat (be patient) and enjoy in a burrito or taco.