In a large skillet, heat the olive oil over medium heat. Add the chopped onion and minced garlic, sautéing until the onion is translucent, about 3-4 minutes.

Add the ground beef to the skillet, breaking it apart with a spoon. Cook until browned, about 5-7 minutes. Drain excess fat if necessary.

Stir in the sliced mushrooms and cook for an additional 5 minutes until they are tender.

Sprinkle the flour over the beef mixture, stirring to combine. Cook for 1-2 minutes to eliminate the raw flour taste.

Gradually add the beef broth, Worcestershire sauce, and Dijon mustard, stirring constantly until the mixture thickens, about 3-5 minutes.

Reduce the heat to low and stir in the sour cream. Season with salt and pepper to taste. Keep warm while you prepare the noodles.

Cook the egg noodles according to package instructions. Drain and return to the pot.

Serve the beef stroganoff over the egg noodles and garnish with fresh parsley.