In a skillet, preheat 3 tablespoons of lard or oil to medium heat. After a minute, add the onions and garlic and sauté for 3-4 minutes.
Tear the chile ancho peppers into smaller pieces. Add the torn ancho peppers and chile de arbol to the skillet with the onions and garlic. Stir frequently until the peppers become aromatic.
Pour in the 2 cups of water to the skillet. Bring to a light simmer, reduce heat to low. Cook for 10 minutes. Cover and remove from the heat and let stand for 10 minutes.
Transfer all skillet ingredients to the blender. Add the orange juice, lime juice, vinegar, cumin, coriander, oregano, 1/2 tsp pepper and 1 tsp of salt into blender. Blend on high until very smooth. If you are not using a power blender like a vitamix, you may need to blend for and extra minute. Taste for salt. Reserve the sauce.
In that same skillet, heat 3 tablespoons of pork manteca(lard) or oil to medium heat for 2 minutes. Add the shredded pork and fry, tossing as needed, until the pork begins to crisp in some spots. Mix in the reserved sauce to the pork. Continue cooking until it reduces and becomes thick. Some people like to add a little more pork lard to fry the pork in the sauce longer. Serve with warm tortillas, cilantro and pickled red onions.