In a small bowl, mix together the salt, onion powder, garlic powder, black pepper and smoked paprika if using. Rub the seasoning blend all over the roast to coat it evenly on all sides.

Turn the Instant Pot on to the Saute function. Once hot, add the oil and sear the seasoned roast for 2-3 minutes per side until browned all over. Remove roast and set aside.

Pour in the beef broth and Worcestershire sauce, using a spoon to scrape up any browned bits from the bottom. Turn off Saute function.

Place the seared roast back into the pot and scatter the potatoes, carrots and onions around it.

Lock the lid in place and set the vent to Sealing. Pressure Cook on High for 60 minutes for a 3 lb roast or 80-90 minutes for a 4-5 lb roast. (See notes if using a frozen roast.)

Once the cook time is up, allow the pot to naturally release pressure for 10 minutes before doing a controlled quick release of any remaining steam.

Carefully remove the lid and transfer the roast and veggies to a platter. Shred the roast into chunks with two forks.

Set the Instant Pot to Soup/Broth setting. Make a slurry by whisking together the water and cornstarch. Once the cooking liquid is simmering, whisk in the slurry and continue stirring until thickened into a gravy. Season with extra salt, pepper or garlic powder as needed.

Serve the shredded pot roast and veggies smothered with the rich gravy. Garnish with parsley or thyme if desired.