1. In a large pot, add beef, beef broth, guajillo chiles, ancho chiles, onion, garlic, bay leaves, cumin, oregano, salt, and pepper. Bring to a boil.
2. Reduce heat to low and simmer for about 3 hours, or until the beef is tender and shreds easily.
3. Remove the beef from the pot and shred it using two forks. Set aside.
4. Strain the broth and discard the solids. Reserve the broth.
5. Heat a skillet over medium heat. Dip each tortilla into the reserved broth, then place in the skillet. Add shredded beef to the tortilla and cook until the tortilla is crispy.
6. Serve the tacos with chopped cilantro, diced onions, and lime wedges.
Notes:
For extra flavor, you can add a bit of the reserved broth to the tacos before serving.