In a large bowl, mix sirloin, salt, pepper, garlic powder, onion powder, paprika. Toss to coat.
Turn Instant Pot to "saute," and add olive oil and sirloin. Sear sirloin on all sides until just barely browned.
Add the mushrooms, onions, and butter. Continue to saute until the mushrooms and onions begin to soften. Add the garlic and saute for about 30 more seconds.
Remove the meat, mushrooms, and onions from the Instant Pot, and place in a large bowl. Toss with flour to coat.
Use the wine to deglaze the Instant Pot. In a small bowl or mixing cup, combine the Worcestershire Sauce, Dijon mustard, and beef broth. Add the mixture to the Instant Pot along with the sirloin and mushroom mixture.
Close the Instant Pot, and set to cook on high pressure for 13 minutes. Meanwhile, make the cornstarch slurry by mixing the cornstarch with 3-4 tablespoons of water. This is also a good time to prepare the noodles or mashed potatoes.
After the beef stroganoff cooks for 13 minutes, allow it to complete a natural release for 10 minutes before opening the steam valve for the quick release.
Remove the lid and add the sour cream (see tips above for tempering). Stir to combine.
Add the cornstarch slurry, and stir to combine.
Garnish with parsley and serve immediately over noodles or mashed potatoes. Store any leftovers in the refrigerator for 2-3 days in an airtight container.