Trim large sections of fat from the roast. Cut into 6-8 pieces. Season with salt and pepper.
Sear the beef - either in a pan or in the Instant Pot. Put the vegetable oil in the pan, and get it hot. Cook each side of the beef chunks for 1 to 2 minutes, until browned. I did this step, but I think it's optional.
Remove the beef and set it aside. Add the onions to the pan and saute until soft. 2-3 minutes.
Add 1 cup beef broth to the pan, and scrape the bottom to get all of the good stuff off the bottom.
Add in tomato paste, green chiles and bay leaves.