Add remaining tablespoon oil, onion, and carrot to Instant Pot and cook, stirring occasionally, until just starting to turn tender, about 4 minutes.
Stir in the flour, cook, stirring, 30 seconds. Stir in wine. Bring to boil and cook until reduced by half, about 1 minute.
Pour ¾ cup water into pot and sprinkle in seasoning packet, stirring to combine, making sure to scrape up all the fond on the bottom of pot. Nestle beef into pot.
Lock lid and set to pressure cook on high for 1 hour.
Follow manufacturer’s guide for quick release, making sure to wait until cycle is complete before unlocking and removing the lid.
Transfer beef to a plate and shred with two forks. Return beef to Instant Pot and stir in rigatoni.
Serve with parsley and Parmesan.
Recipe by 5* trending recipes with videos at https://food.theffeed.com/2019/11/25/pot-roast-pasta/