Mince the garlic finely. In a large pot or skillet, melt the butter over medium heat and add the minced garlic. Sauté for about one minute, or until softened.

Add the ground beef to the pot. Cook until fully browned, breaking it up with a spatula.

While the beef is cooking, slice the mushrooms. Once the beef is browned, add the mushrooms and black pepper. Sauté for about five minutes until the mushrooms are soft.

Add the uncooked egg noodles, beef broth, Worcestershire sauce, and Dijon mustard to the pot. Stir gently.

Cover the pot with a lid, bring to a boil over medium-high heat, then reduce to low and simmer for 7-10 minutes, stirring occasionally, until noodles are tender and liquid is mostly absorbed.

Stir in the sour cream until the mixture is rich and creamy. Adjust seasoning with salt and pepper if necessary.

Sprinkle chopped parsley over the dish and serve warm.