Prepare the Sauce: Begin by toasting the guajillo and pasilla peppers in a dry skillet over medium heat. Keep an eye on them for about 2-3 minutes until they release their aroma and darken slightly. Transfer them to a blender.
Blend the Sauce: To the blender with the peppers, add the quartered onion, minced garlic, ground cumin, dried oregano, smoked paprika, apple cider vinegar, and 1 cup of beef broth. Blend the mixture until it is silky smooth and free of lumps. Set the flavorful sauce aside.
Sear the Meat: In a large pot or Dutch oven, heat a tablespoon of oil over medium-high heat. Generously season the beef chunks with salt and pepper. Working in batches, sear the beef until it is beautifully browned on all sides—about 4-5 minutes per batch. Remove the beef from the pot and set aside.
Simmer: In the same pot, pour in the blended sauce and let it bubble for 3-4 minutes while stirring frequently to deepen the flavors. Return the seared beef to the pot, pour in the remaining beef broth, and let everything come to a gentle simmer. Cover the pot and reduce the heat to low, allowing it to cook for about 2-3 hours, or until the meat is fork-tender and easily shreds.
Shred the Beef: After the beef is cooked to perfection, take it out of the pot and shred it finely using two forks. Once shredded, return it to the pot and stir well, ensuring the beef absorbs all the juicy flavors.
Prepare the Tacos: Heat a dry skillet over medium heat. Warm each tortilla for about 30 seconds on each side, or until they are soft and pliable. Fill each tortilla generously with the succulent birria, topping with fresh chopped cilantro and diced onions for added crunch and flavor.
Serve: Present the tacos with lime wedges on the side for a zesty squeeze, and serve with small bowls of the reserved broth for dipping, making each bite an interactive experience.
Notes
Serve with lime wedges and extra broth for dipping.