Preheat your oven to 350°F (175°C).
In a large skillet, heat olive oil over medium heat. Add diced onion and minced garlic, sautéing until the onion is translucent.
Add the ground beef to the skillet, breaking it apart with a spatula. Cook until browned, about 5-7 minutes. Drain excess fat if necessary.
Stir in the sliced mushrooms, Worcestershire sauce, and Dijon mustard. Cook for an additional 3-4 minutes until the mushrooms are tender.
Pour in the beef broth and bring the mixture to a simmer. Reduce heat and stir in the sour cream until well combined. Season with salt and pepper to taste.
In a large mixing bowl, combine the uncooked egg noodles with the beef mixture, ensuring the noodles are well coated.
Transfer the mixture to a greased 9×13 inch baking dish. Spread evenly and top with shredded cheddar cheese.
Cover the dish with aluminum foil and bake in the preheated oven for 20 minutes.
Remove the foil and bake for an additional 10 minutes, or until the cheese is bubbly and golden.
Remove from the oven and let it cool for a few minutes. Garnish with fresh parsley before serving.