Heat lard in a pan over medium-low heat. Add first the peppercorns, garlic, cumin seeds, and cinnamon stick. Stir for half a minute.
Add guajillo chilies, and cook for 1 minute while stirring constantly.
Stir in tomatoes and onions. Cook for 4 minutes or until onions soften and tomatoes release their juices.
Add vinegar and 1 cup of hot water, then add the oregano, salt, and chiles de árbol.
Mix well, turn off the heat, cover, and allow to soak for 10 minutes.
Place all ingredients in a blender and blend until you’ll have a silky smooth sauce. Allow the sauce to cool down completely.
Marinate
Place chicken in a baking dish, and add the birria sauce through a medium sieve over the chicken.
Turn the chicken well to coat all sides.
Cover with cling film and store in the fridge for at least 8 hours and up to 24.
Cook
Place chicken and all the remaining marinade in your Instant Pot and pour 3 cups of water.
Add bay leaves and salt.
Cook at high for 25 minutes then naturally release pressure for 30 minutes.
Serve as a main dish
Remove the chicken from the pot and divide it into serving bowls.
Ladle the birria consommé and top with chopped cilantro and onion.
Serve with chili oil, lime wedges, and warm corn tortillas.
Make the tacos with consommé
Remove the chicken from the pot and shred it with two forks. Set aside.
Heat a griddle or a non-sticking pan until smoky.
Take one tortilla and quickly dip it into the grease of your chicken birria.
Place 2-3 tortillas (previously dipped in the oil) on the skillet and heat for about 30 seconds flipping two times to heat them up.
Put some cheese and chicken in the middle of each tortilla.
Fold the tortillas into half-moons and keep cooking until the cheese has melted nicely and the tortillas are a bit crispy.
Place tacos on a platter, carefully open them a little and add some onions and cilantro in the middle.
Serve with lime wedges, chili oil, and a small bowl of the birria consommé to dip the tacos in.
Notes
Using a slow cooker: Place the marinated chicken in your slow pot, add water to cover about 1 inch (2.5cm), and cook for 3 hours on high or 5-6 hours on low.
On the stovetop: Place the meat in a large pot and cover it with 1.5 inches of water. Simmer for about 1 hour or until chicken is nicely cooked through.
Cook in the oven: For cooking in the oven, place chicken and cover with 1-inch of water, cover with foil, and cook at 375°F (190°C) for about 1 and a half hours or until the chicken meat is falling from the bones.
Substitute the chilies: If you can’t find guajillo chilies where you live, use other types of mild-spicy dried red chilies such as Anaheim, Hatch, or California.
Make it thicker: Want a thicker birria sauce instead of brothy? Add 2 more tomatoes and reduce the amount of water to barely cover the meat.