Cook the Noodles: In a large pot, bring water to a boil and cook the egg noodles according to package instructions. Drain and set aside.
Brown the Beef: In a large skillet, cook the ground beef over medium heat until browned. Remove from the pan, drain any excess fat and set aside.
Add Aromatics: To the empty skillet, add the chopped onion and minced garlic. Cook until the onions are translucent, about 5 minutes.
Season: Add in pepper and stir in the dry Au Jus gravy mix.
Add Liquids: Pour in the beef broth and stir to combine. Next, add the cream of mushroom soup and sour cream to the skillet. Bring the gravy mixture to a simmer and cook over medium heat for about 3 minutes to thicken.
Combine with Beef & Noodles: Add the cooked noodles and ground beef back to the skillet with the gravy and gently fold them in until everything is well combined.
Cheese Time: Remove from heat and sprinkle the shredded cheddar cheese over the beef stroganoff. COver with lid and let it melt and blend into the sauce.
Serve: Serve hot, garnished with chopped fresh parsley if desired.