Cut the roast in half if necessary to fit into the Instant Pot
Season each half of the roast with salt, pepper, granulated garlic, dried oregano and red pepper flakes
Turn the Instant Pot on "saute"
Slice the red and green bell pepper and saute it them in the Instant Pot until softened. Set aside until ready to use
Brown the beef halves one at a time on all sides.
Pour beef broth into the Instant Pot with the beef halves and cook on the "Meat/Stew" setting for 60 minutes
Shred the beef and serve it on hero rolls with giardiniera and sauteed peppers
OR Chill the beef and broth in the refrigerator overnight then slice the beef and reheat it in the broth.
Serve it on hero rolls with giardiniera and sauteed peppers