Follow these easy steps to create delicious Crock Pot Birria Tacos:

1. Toast the Chiles: In a dry skillet over medium heat, briefly toast the guajillo and ancho chiles until fragrant. This should take about 1-2 minutes. Remove from heat and let cool.

2. Soak Chiles: Once cooled, remove the stems and seeds. Place the chiles in a bowl and cover them with hot water. Let them soak for about 15 minutes until softened.

3. Blend the Marinade: In a blender, combine the softened chiles, garlic, onion, oregano, cumin, cinnamon, salt, pepper, and apple cider vinegar. Blend until smooth, adding a bit of soaking water if necessary.

4. Prepare the Beef: In your slow cooker, add the chunks of beef. Pour the blended marinade over the meat, ensuring it is well-coated.

5. Add Broth: Pour the beef broth into the slow cooker, stirring to combine. Cover the slow cooker with the lid.

6. Cook the Meat: Set your slow cooker to low for 6-8 hours, or high for 4-5 hours, until the beef is incredibly tender.

7. Shred the Beef: Once cooked, remove the beef from the slow cooker. Using two forks, shred the beef into bite-sized pieces.

8. Prepare the Consommé: Strain the liquid from the slow cooker into a separate bowl or serving dish. This will be used as the broth for dipping.

9. Warm Tortillas: In a hot skillet, warm the corn tortillas for about 30 seconds on each side until soft and pliable.

10. Assemble the Tacos: Fill each tortilla with shredded beef, then top with chopped cilantro and diced onions.

11. Serve with Consommé: Serve the tacos with a small bowl of the broth on the side for dipping.