Heat the oil until shimmering in an Instant Pot set to Sauté mode - High (use medium high heat with a stove top PC), about 3 minutes. Add the seeded and stemmed dried Ancho and Guajillo peppers, stir to coat with oil, and toast for 1 minute. Add the onion, tomatoes, garlic cloves, cinnamon, bay leaf, black pepper, cumin, coriander, oregano, and cloves, and stir in the water and 1 teaspoon of fine sea salt. Lock the lid and pressure cook on high for 4 minutes (Use Manual, Pressure Cook, or Pressure Cook - Custom mode on an Instant Pot), then quick release the pressure.

Unlock the pressure cooker lid and pour everything from the pressure cooker into a blender. Add 2 cups of cold water and white vinegar. Remove the vent plug from your blender lid (if it doesn't have an auto-venting plug), and hold down the lid tight with a towel. (The hot liquid will want to push the lid off the blender when it starts.) Starting on low, slowly ramp the blender up to high speed, then blend on high until completely smooth, 1-2 minutes depending on your blender. Leave the adobo in the blender for now.

Wipe out the Instant Pot (or swap in a second Instant Pot inner pot.) Sprinkle the beef short ribs and chuck with 1½ teaspoons of salt, then put them in the pot. Pour in the adobo from the blender, and stir to coat the beef. Pour in the 6 cups of water and 1 tablespoon of fine sea salt, and stir again.

Lock the lid and cook at high pressure for 45 minutes in an Instant Pot or other electric pressure cooker (use Manual, Pressure Cook, or Pressure Cook - Custom mode in an Instant Pot), or for 40 minutes in a stovetop pressure cooker. Let the pressure come down naturally, 20-30 minutes. (If you're in a hurry, you can quick release any remaining pressure after 15 minutes).

Unlock the lid on the cooker. Scoop the beef out of the broth with a slotted spoon, and transfer it to a platter. Shred the beef on the platter (I use a pair of forks to shred). Shred the beef with a pair of forks.

Heat a large frypan or griddle over medium-high heat. Warm a tortilla on the griddle until softened, about 1 minute. Dip the tortilla in the broth, then put it back on the griddle. Top the tortilla with a lot of shredded Monterey Jack in an even layer, slightly overflowing the edges. Add a smaller pile of shredded beef to the middle of the tortilla, then fold the tortilla in half to enclose the beef. Cook until browned on the bottom, then flip and brown the other side. Transfer to a platter, then repeat for all the rest of the tortillas. Ladle out a mug of broth for each diner, and sprinkle diced onion and cilantro into each mug. Serve, and tell everyone to dip the birria tacos in the cup of broth. Enjoy!