Pat the beef dry with paper towels and season with salt and pepper.
Select SEAR/SAUTE and set the time to 30 minutes. Press START.
When the preheating has finished, add 3 tbsp of oil into the Inner Pot. Once oil starts to smoke, sear the meat brown on all sides for 8-10 minutes. Transfer beef to a large bowl.
Add onions and cook until softened, 6-7 minutes, stirring often. Stir in the garlic and cook for 30 seconds until fragrant, then add the mushrooms and sauté slowly for 5 minutes.
Add 1 cup of beef broth and red wine and whisk well. Scrape up brown bits from the bottom and smooth out any lumps. Press CANCEL.
Return the beef to the Inner Pot, along with any juices from the beef. Stir well.
Select SLOW COOK-Custom-High and set the time for 4 hours. Press START.
Close the Pressure Cooking Lid on the pot and set to VENT.
When slow cooking is complete, remove lid, select SEAR/SAUTE-Low and set the time to 30 minutes. Press START. Mix the 1/2 cup of beef stock and the cornstarch and stir in, combine constantly until sauce is reduced and thickened, beef will soften slightly more during this step.
Add the cream cheese and sour cream, stirring until a smooth sauce is formed. Season with salt and pepper to taste.
Serve with some mashed potato if desired, garnish with fresh parsley.