Season the top, bottom and sides of the roast with Kosher Salt.
Turn your Instant Pot to sauté and add 1-2 tablespoons of vegetable oil. Sear the chuck roast for 3-4 mins per side, then remove and cut into large chunks.
While the Instant Pot is still hot, add 1 tablespoon oil, chopped carrots, and sliced onion. Sauté for 3 minutes then add the garlic, ancho chili powder, cumin, Mexican oregano, and kosher salt. Cook for one more minute.
Turn off the Instant Pot and add the beef broth, dried guajillo chillies, and bay leaves, Stir slightly, scraping the spices from the bottom of the Instant Pot with a wooden spoon.
Place the roast chunks back into the Instant Pot with the liquid and place the lid on, turning the valve to seal. Pressure cook on high for 40 minutes then allow to naturally release for 15 minutes.
Release the remaining pressure if necessary and take off the lid. Remove the beef and shred.
Use an immersion blender to blend the consommé sauce in the Instant Pot or pour into a regular blender and blend. Return the sauce and shredded beef back to the Instant Pot and season with more salt and pepper if needed.