Step 1

Cut the beef across the grain into thin, bite sized strips, about 1 1/2 inches by 1/2 inch. Heat a large skillet over high medium high heat. Melt 1 tablespoon of butter and add half the beef. Cook until well-browned, about 2-3 minutes per side. Remove beef from pan to a shallow dish and repeat steps with 1 more tablespoon of butter and remaining beef.

Step 2

Lower heat to medium and add remaining 2 tablespoons of butter to the empty pan. Stir in mushrooms and onion and season with 1/2 teaspoon salt. Cook until soft and dark golden brown, stirring occasionally, about 5 minutes. Stir in garlic and cook for an additional minute.

Step 3

Sprinkle vegetables with flour and cook for 1 minute. Add beef broth, optional Dijon and Worcestershire sauce, and stir until smooth. Bring to a simmer and cook until thickened, about 5 minutes. Return the beef to the pan, along with any juices and stir in the sour cream. Season to taste with salt and pepper. Heat until hot, but do not boil. Garnish with parsley and serve over hot egg noodles.