Set the Instant Pot to sauté and add olive oil to bottom of the Instant Pot insert.
Add the beef chuck roast and cook until just browned outside.
Next, add stock, oregano, garlic, onion, paprika, Italian seasoning, salt and pepper, and pepperoncini juice. Stir to combine.
Place the lid on the Instant Pot, turn the valve to the sealing position, and set to manual pressure / high pressure for 30 minutes.
When cook time is done, perform a quick pressure release. Open the lid and use two forks to roughly shred the beef.
Stuff the sandwich rolls with the beef and top with chopped peppers.
Notes
Choose a flavorful cut of beef such as beef chuck roast, sirloin tips or beef stew meat.
Cut larger pieces of beef into chunks.
Use a paper towel to pat the beef dry before you sauté it. This will help create a deep delicious flavor.
Season generously.
Before pressure cooking, take a moment to sear the meat. This extra step locks in juices and adds a caramelized layer of flavor to the beef. Simply set your Instant Pot to sauté mode, add a bit of oil, and brown the meat on all sides.
Add sliced onions and peppers if you like.
Pepperoncini juice adds a bit of heat, so use less for a milder flavor.
If not using the pepperoncini juice be sure to add additional beef stock or even red wine to ensure the instant pot has enough liquid.
After cooking, let the beef rest for a few minutes before shredding. Use two forks to pull the meat apart effortlessly, taking advantage of its newfound tenderness.
The cooking time listed does not include time for the Instant Pot to come up to pressure or for the pressure to release.