In a large skillet, heat over medium heat until hot. Add the ground beef, breaking it apart with a spatula, and cook until browned, about 6–8 minutes. Drain any excess fat to ensure the stroganoff remains creamy and not greasy. Set the browned beef aside while you prepare the vegetables.

In the same skillet, add the chopped onion and sliced mushrooms. Sauté them until the onion becomes translucent and the mushrooms are tender, about 5 minutes, stirring occasionally to prevent browning. Then, add the minced garlic and cook for an additional minute until fragrant.

Sprinkle the flour evenly over the beef and vegetable mixture, stirring to incorporate and eliminate any lumps. Gradually pour in the beef broth and Worcestershire sauce, stirring continuously for about 3-4 minutes until the sauce thickens and becomes glossy.

Reduce the heat to low and stir in the sour cream, mixing until the sauce is smooth and creamy, about 2 minutes. Taste the sauce, adding salt and pepper as needed to enhance the flavors.

Prepare the egg noodles according to the package instructions, then drain them well. Serve the creamy beef mixture over the noodles, garnishing with chopped parsley before serving.