1. Pat beef dry and toss with flour, salt, and pepper until evenly coated.

2. Heat olive oil and 2 tablespoons butter in a large skillet over medium-high heat.

3. Add beef in batches and sear 1–2 minutes per side until browned. Remove and set aside.

4. Add remaining butter to the skillet and sauté onions over medium heat until soft, about 5 minutes.

5. Add mushrooms and cook 7–10 minutes until browned and moisture has evaporated.

6. Stir in garlic and cook 1 minute until fragrant.

7. Pour in beef broth, scraping up browned bits from the pan.

8. Whisk in Dijon mustard and Worcestershire sauce. Bring to a gentle simmer.

9. Simmer sauce for 5 minutes until slightly thickened.

10. Reduce heat to low and return beef and juices to the skillet.

11. Warm beef gently for 2–3 minutes without boiling.

12. Remove skillet from heat. Temper sour cream with a few tablespoons of hot sauce.

13. Stir tempered sour cream into the skillet until smooth and creamy.

14. Taste and adjust seasoning with salt and pepper if needed.

15. Serve immediately over egg noodles and garnish with parsley or dill.