Step 2: Sear the Fillet

4. Heat a large frying pan over medium-high heat and add 1 tbsp of butter or olive oil.
5. Sear the fillet strips in batches, cooking for about 2 minutes per side until browned but not overcooked. Remove and set aside.

Step 3: Cook the Mushrooms and Aromatics

6. In the same pan, add the remaining butter or oil and sauté the onions until translucent.
7. Add the mushrooms and cook until they release their juices and become golden brown.
8. Stir in the minced garlic and cook for another 30 seconds until fragrant.

Step 4: Make the Sauce

9. Sprinkle in the flour (if using) and stir well to coat the mushrooms and onions.
10. Pour in the broth and let it simmer for a couple of minutes, allowing it to reduce slightly.
11. Stir in the heavy cream, Dijon mustard, Worcestershire sauce, smoked paprika, salt, and black pepper.
12. Simmer for 5 minutes until the sauce thickens.