Bring a large pot of salted water to a boil over high heat. Add the egg noodles and cook according to package instructions until al dente, about 7-9 minutes. Once cooked, drain the noodles in a colander and set aside. Drizzling a bit of olive oil over the noodles can help prevent them from sticking together.

In a large skillet, heat 2 tablespoons of olive oil over medium-high heat. Once the oil shimmers, add the beef strips and cook for 5-7 minutes until they are well-browned on all sides. Use tongs to turn the beef for even cooking. Remove the beef from the skillet and place it on a plate, allowing it to rest while you prepare the sauce.

In the same skillet, add the diced onions and minced garlic, cooking for about 2-3 minutes until they are translucent and fragrant. Stir occasionally to prevent sticking. Next, add the sliced mushrooms to the skillet, sautéing for an additional 5 minutes until they are tender and browned, which will release their lovely umami flavor.

Pour in 1 cup of beef broth, followed by the Worcestershire sauce and Dijon mustard, stirring well to combine. Increase the heat slightly to bring the mixture to a gentle simmer. Allow the sauce to bubble away for about 5 minutes, which will deepen the flavors and slightly reduce the liquid.

Reduce the heat to low, and gradually stir in the sour cream until fully incorporated, creating a rich, creamy sauce. Season the mixture with salt and pepper to taste, ensuring all flavors balance perfectly. Take care to keep the sauce warm without boiling to prevent curdling.

Return the sautéed beef to the skillet, mixing gently until the beef is fully coated in the creamy sauce and heated through, about 2-3 minutes. Serve the delicious Beef Stroganoff over the cooked egg noodles, allowing each bite to capture the heartwarming essence of this family favorite.