Toast the dried chiles in a dry skillet over medium heat for 2-3 minutes until fragrant. Remove and soak in hot water for about 15 minutes until softened. Blend the chiles with chopped onion, cumin, garlic, and approximately 2 cups of the soaking water until smooth.

In a pot, heat oil over medium-high heat. Cut the beef into chunks, pat dry, and season with salt. Sear the beef in batches for about 4-5 minutes each side until caramelized. Remove the beef and set aside.

Return the browned beef to the pot and pour the blended broth over. Stir to coat. Cover and reduce heat to low, simmer for about 4 hours until fork-tender.

Shred the beef into pieces using forks. Heat corn tortillas in a clean skillet for about 30 seconds on each side until warm. Fill each tortilla with shredded beef and sprinkle with cheese.

Serve hot, garnished with cilantro and diced onions, alongside the rich consommé for dipping.