Begin by bringing a large pot of salted water to a boil. Add the egg noodles and cook according to the package instructions until al dente. Drain and set aside.
In a large skillet, heat the olive oil over medium-high heat. Add the thinly sliced beef sirloin to the skillet in a single layer. Season with salt and pepper. Sear the beef for about 2-3 minutes per side until browned. Remove the beef from the skillet and set aside.
In the same skillet, add the chopped onion and sauté for about 2-3 minutes until translucent. Add the minced garlic and sliced mushrooms, cooking for an additional 5-7 minutes until the mushrooms are tender and have released their moisture.
Pour in the beef broth and Worcestershire sauce, scraping up any browned bits from the bottom of the skillet. Bring the mixture to a simmer and cook for about 5 minutes to allow the flavors to meld.
Reduce the heat to low and return the cooked beef to the skillet. Stir in the sour cream, mixing until well combined. Cook for another 2-3 minutes until heated through. Adjust seasoning with salt and pepper as needed.
Toss the cooked egg noodles in the skillet with the beef stroganoff sauce until well coated. Serve hot, garnished with freshly chopped parsley for a pop of color and freshness.