Cook the beef. Combine the 2 pounds of cubed chuck roast, 2 pounds beef shank, the sliced onion, 6 garlic cloves, the 2 tablespoons of salt, the 3 bay leaves and the 1 tablespoon oregano in a large soup pot. Cover with water by 2-inches and bring to a boil over medium-high heat.

Reduce heat to medium-low and skim off any foam. Cover and simmer until beef is very tender, about 3-4 hours.

Blanch the hominy. Fill a 6-quart pot halfway with water and bring to a boil over high heat. Drain and rinse the 2 cans of hominy. Once the water is boiling add the hominy and let the water return to a boil. Drain and rinse once more with cold water. Set aside.

Toast and soak chiles. Meanwhile, place the 2 ancho chiles and 4 guajillo chiles in a dry cast iron frying pan or comal and toast on all sides until darker in color and fragrant. Bring a small saucepan of water to a boil and submerge the toasted chiles in the boiling water. Remove from the heat and let soak until the chiles are soft, about 30 minutes.

Make sauce. Using kitchen tongs, remove the chiles from the water and place in a blender (save the chile water). Add the 1 chopped onion, the 3 cloves garlic, the teaspoon of cumin, the 2 whole cloves, and the 2 tablespoons of salt, and about 1/2 cup of the chile soaking liquid. (This will be very salty but it will end up flavoring the whole soup so don't be alarmed). Blend on high until smooth (you may need to add more soaking liquid to get the blender moving). Set aside while you shred the beef.

Shred the beef. Once beef is tender and the meat on the shank easily pulls away from the bone with a fork, remove the beef shank from the broth to a large plate or baking sheet and set aside to cool. Once beef is cool enough to handle, shred into bite-sized pieces, removing any gristle or fat or bone.

Strain broth. Set a strainer over a large bowl or pot big enough to hold the broth. Strain broth into the bowl. Place all the pieces of beef with the meat you just shredded. Discard the remaining solids and wash out the pot you cooked the beef in.

Fry the sauce. Heat the 2 tablespoons of oil in the pot you used to cook the beef in over medium-high heat. Carefully pour the chile sauce into the hot oil (it will splatter) and stir until sauce is fragrant and fried, about 5-15 minutes.

Finish soup. Return beef to the pot with the sauce. Add the strained broth and hominy and bring to a simmer. Taste and add more salt if needed.

Serve. Ladle into big bowls and serve with as many of the garnishes as you'd like. I think it is best to arrange all the garnishes on a big platter and set it in the middle of the table for everyone to help themselves.