Prepare, chop, and measure the ingredients.

Choose the sauté button and add the olive oil to the Instant Pot. When the oil is hot and shimmering, add the beef, kosher salt, and pepper. Cook, stirring, for 6 to 8 minutes or until the beef is browned on all sides. Remove the beef to a plate.

Add 1 tablespoon of butter to the pot. When the butter is melted and sizzling, add the onion and mushrooms. Sauté for 2 minutes. Add the garlic and sauté for 1 minute longer.

Add the beef back to the pot along with the beef broth, Worcestershire sauce, and mustard. Stir, scraping up any stuck-on browned bits. If you leave and burnt bits, you could get a "burn notice."

Lock the lid in place and ensure the knob/valve is in the sealing position. Select pressure cook and set the time for 10 minutes. When the time is up, let the pressure come down naturally for 5 minutes then do a quick release.

Add the noodles to the pot and replace the lid. Select pressure cook and set the timer for 5 minutes. When the time is up, do a quick release and remove the lid.

Combine the remaining butter with the flour and stir or knead until well blended. Stir the butter and flour mixture into the noodles and choose the sauté function. Add the sour cream and continue cooking for about 2 minutes or until thoroughly heated. Do not boil.

Transfer the beef stroganoff to a serving bowl and garnish with parsley.

Enjoy!