Prepare the chilies by trimming the stems from the ancho and guajillo peppers. Next, empty each chile's interior seeds into a big basin by shaking them out. Pour boiling water over the chiles, making sure they are well immersed, then let them to soak and rehydrate. Proceed with the recipe in the meanwhile.
To brown the pork, put the oil in a large stockpot or Dutch oven and heat it to medium-high. When the saucepan is heated, slowly rotate it to coat the bottom equally. Add a few of the pork chunks to the saucepan in stages, being cautious not to pack it too full. Sear the pork for two to three minutes on each side, or until a good sear forms. Add salt and pepper to taste when preparing the meat. Once all of the pork is browned, transfer it to a fresh plate or small baking sheet and continue cooking. After that, turn down the heat to medium and save the browned pork bits.
Add the chopped onion to the saucepan and sauté the aromatics. Sauté the onions for three to four minutes, stirring occasionally, or until they are soft. After that, add the garlic and simmer for a further minute or so, or until the combination becomes aromatic.
Blend the chiles: Going back to the soaked chiles, add 1 cup of the soaking liquid and the soaked chiles to the body of a powerful blender or food processor; do not discard the remaining liquid. Process until the chiles are smooth, about 1 minute. If the mixture seems too thick, add a little more of the soaking liquid (or to help swish/clean out the blender/processor).
To make the pozole rojo, add the pork back into the pot once it has browned and any accumulated juices. Blend the chile combination and add it to the saucepan with the hominy, broth, bay leaves, cumin, oregano, and chipotle powder (if using). After thoroughly mixing, turn up the heat to medium-high and gently boil.
Sim-sima: Lower the heat to medium-low and simmer the stew for one and a half to two hours, stirring the pozole periodically, or until the pork is extremely soft and easily pulls apart.
Serve: After the stew has simmered, remove the bay leaves, taste it, and adjust the seasoning with extra salt or pepper if needed. Spoon pozole rojo into serving bowls and garnish with shredded cabbage, sliced jalapeños or radish, cotija cheese, diced avocado, lime wedges, and/or freshly chopped cilantro, if preferred. Have fun!