Instructions:

• Step 1: Prepare the Steak
  Start by bringing your beef filet to room temperature. Season it generously with salt on both sides. This will enhance the flavor and help to form a delicious crust when seared.
• Step 2: Sear the Steak
  In a heavy-bottomed skillet, melt 1 tablespoon of butter over medium-high heat. Once the butter is melted and bubbling, carefully add the steak to the skillet. Sear for about 3-4 minutes on each side for medium-rare, or until your desired doneness is reached. Use a meat thermometer to check for an internal temperature of 130°F for medium-rare.
• Step 3: Rest the Steak
  Once cooked, remove the steak from the skillet and transfer it to a cutting board. Tent it loosely with aluminum foil and allow it to rest while you prepare the sauce.
• Step 4: Make the Mushroom Sauce
  In the same skillet, add the remaining tablespoon of butter. Add the minced shallots and sauté for about 1 minute until fragrant. Then, add the sliced mushrooms and cook until they release their moisture and become golden brown, about 5-7 minutes.
• Step 5: Deglaze with Marsala
  Pour the dry Marsala wine into the skillet, scraping up any browned bits from the bottom for added flavor. Allow the wine to simmer for about 2-3 minutes until it reduces slightly.
• Step 6: Add Cream and Season
  Stir in the Dijon mustard, heavy cream, and Worcestershire sauce. Allow the sauce to simmer for another 2-3 minutes until it thickens slightly. Taste and adjust seasoning if necessary.
• Step 7: Serve
  Slice the rested steak against the grain and arrange it on plates. Spoon the creamy mushroom sauce over the top and garnish with minced parsley. Serve immediately and enjoy your restaurant-quality meal at home!