Season the brisket on both sides with carne asada seasoning.
Preheat 2-3 tablespoons of oil in a large skillet at medium heat.
To the bottom of the pressure cooker, sliced onion, add the beef broth or water, garlic, onion, bay leaves, bouiilon, maggi and peppercorns. Turn heat to medium/low.
Sear the brisket in the hot oil for 4-5 minutes per side. Transfer to the pressure cooker.
Secure and lock the lid. Turn heat to high. When it comes up to pressure and the safety valve locks wait for the steam release knob to begin to rotate. As soon as it does, turn heat down to medium/low and set your timer for 1 hour.
When time is up, carefuuly move cooker off of the heat. When the safety valve unlocks, remove brisket onto board. It will shred alot easier if you do this while the brisket is hot. Using two forks, finely shred the brisket. Cover and store until ready to use.