Place the stemmed and seeded guajillo, ancho, and chipotle chiles flat in a dry skillet over medium heat and toast for about 30 seconds per side, until fragrant and pliable but not blackened.
Transfer the chiles to a bowl, cover with 4 cups (950 ml) hot water, and soak for 15 to 20 minutes until soft, then drain.
Place the tomatoes on a sheet pan and broil for 8 to 10 minutes, turning once, until the skins blister and char in spots.
Add the drained chiles, onion, garlic, broiled tomatoes, 2 cups (475 ml) beef broth, vinegar, oregano, cumin, thyme, 1 tsp salt, and 1/2 tsp pepper to a blender and blend until completely smooth.
Cut the chuck roast into 3 or 4 large chunks, season all over with salt, and place in a large pot or Dutch oven. Pour the sauce over the beef, add the bay leaf, and add extra broth or water until the beef is mostly submerged.
Bring to a boil over medium-high heat, then reduce to low, cover, and simmer for 2 1/2 to 3 hours, until a fork twists through the beef with no resistance. The beef will be far past the safe 145°F (63°C) for whole beef cuts by this point.
Remove the beef to a cutting board, shred it with two forks, and return it to the pot for 5 minutes to soak up the sauce.
Lift the shredded beef out with a slotted spoon and let it drain in a colander. Strain the remaining liquid into a saucepan, discard the bay leaf, season with salt, and keep warm over low heat as the consommé.
Spread butter on one side of each bread slice and lay 6 slices buttered side down.
Top each of the 6 slices with a layer of Oaxaca, a portion of drained beef, a little cheddar if using, and more Oaxaca, then close with the remaining slices, buttered side up.
Cook the sandwiches in batches in a skillet over medium heat for 3 to 4 minutes per side, until the bread is deep golden and the cheese is fully melted. Lower the heat and cover the pan for 1 minute if the bread browns before the cheese melts.
Slice the sandwiches diagonally, sprinkle with cilantro, and serve hot with bowls of warm consommé and lime wedges for dipping.