01 - Bring a large pot of salted water to a boil. Add egg noodles and cook according to package instructions until al dente. Drain and set aside.
02 - In a large skillet over medium heat, add mushrooms and onion. Cook, stirring occasionally, until softened and lightly browned, about 6–8 minutes.
03 - Sprinkle flour evenly over the vegetables. Stir to coat and cook for 1 minute to remove raw flour flavor.
04 - Pour in vegetable broth, stirring constantly to dissolve flour. Allow the mixture to simmer for 3–4 minutes or until slightly thickened.
05 - Reduce heat to low and blend in sour cream. Mix until the sauce is smooth and gently heated through. Season with salt and black pepper to taste.
06 - Add cooked egg noodles to the skillet and toss to evenly coat with the creamy mushroom sauce. Serve immediately.