Press the Sauté button on your Instant Pot and heat the olive oil until it shimmers. Add the beef sirloin and brown for 2 to 3 minutes until no longer pink.

Stir in the chopped onion and minced garlic, sauté for another 2 minutes until the onion is translucent.

Add the sliced mushrooms and cook for 4 to 5 minutes until they release moisture and brown slightly.

Pour in the beef broth, Dijon mustard, Worcestershire sauce, paprika, salt, and black pepper. Stir well.

Cancel the Sauté function, secure the lid, set the valve to Sealing and select Pressure Cook on High for 8 minutes.

Prepare the egg noodles according to package instructions and set aside.

Once pressure is released, stir in the sour cream until fully combined.

Mix cornstarch with cold water to form a slurry, stir into the pot and press Sauté again. Cook for 2 to 3 minutes to thicken.