Set the pressure cooker to SAUTÉ. Add vegetable oil and when it gets hot, sear the meat cubes or strips turning them quickly until browned (about 30 seconds). Set aside on a plate.

• Add butter and when it gets melted, add onion to the pot. Sauté until softened and translucent. 
• Add the mushrooms and sauté until golden. Stir in flour until evenly incorporated. 
• Deglaze the pot with beef broth. And using a wooden spoon, scrape off any bits stuck to the bottom of the pot. Then, put the meat back into the pot. 
• Add Dijon mustard and season with salt and pepper. Cover with the lid and set the valve on. Press PRESSURE COOK or MANUAL on high for 4 minutes. 
• When cooking time is up, allow for natural release of steam for 2-3 minutes, then quickly release the remaining steam. 
• Add the egg noodles making sure that they stay on top of the rest of the ingredients. Add more broth or water if the stock is not covering them completely. Seal the Instant Pot and cook on High PRESSURE or MANUAL for 4 more minutes. 
• When the cooking time is up, allow for natural release of steam for 2-3 minutes, then quickly release the remaining steam. 
• Finally, mix sour cream with a little of hot sauce in a cup or a small bowl. Then stir it into the rest of the ingredients in the Instant Pot. This will prevent the sour cream from curdling if added directly to hot liquid. Adjust salt and pepper to taste.
• To thicken the sauce, press on SAUTE and once the sauce comes to a boil add the cornstarch slurry (1 tablespoon cornstarch mixed with 1 tablespoon of cold water). Whisk until the sauce is thickened (it thickens very quickly). Serve warm and enjoy!