Cook the egg noodles according on the package directions. Drain and put aside.
Heat the olive oil on medium-high-heat in a large pot. Then add the ground beef and cook and crumble till it is browned and cooked through. Season with desirable amounts of pepper and salt.
Remove the cooked-beef from the pot and put aside, leave the grease from the pan.
Add the onion into the pan and then sauté over moderate heat for 5 minutes or till tender.
Add the minced garlic and cook for extra minute, till aromatic and then add the butter into the pan and swirl around till it is melted.
Use a fork to stir into the flour and cook for a minute, stirring continuously. Then stir in half the beef broth till incorporated, then put in the next half.
Use a spatula to scrape the brown bits in the bottom of the pan, then that will provide the sauce lots of taste.
Mix in the sour cream, mustard, and half the cheese till well-combined. (Sour cream will keep melting & will gradually integrate in the mix) Let it simmer for 3-5 minutes, till thickened.
Add the ground beef back into the sauce and use a silicone-spatula to combine the egg noodles.
Pour into a 9×13″ greased casserole-dish and top with remaining cheese.
Bake uncovered at 375° for 15-20 minutes, till the cheese is melted and hot.
Serve and top with chopped parsley.
