Put the beef roast into the Instant Pot. Add enough water to reach the top of the roast.
Add the celery salt, Worcestershire Sauce, beef soup base, chopped onion, onion soup mix and Cream of Mushroom soup.
Set the Instant Pot to Meat/Stew for 45 minutes. Typically a roast doesn’t take this long but this is so we can shred it when it is done.
Remove roast from Instant Pot, and shred.
Return the shredded beef back into the Instant Pot, and add the pack of frozen egg noodles. Turn the Instant Pot to Saute for 5 minutes.
Cover the Instant Pot with the lid, and let sit for 10 minutes until the noodles are no longer frozen, and are puffed up a bit.
Taste. If it needs salt and pepper, add it.
Serve. If desired, add grated Parmesan Cheese.
