Ingredients:

  • 1 Beef Tenderloin Roast (approx. 3 lbs / 1.35 kg)
  • 2 Tbsp Olive Oil
  • 1 Tbsp Kosher Salt
  • 1 tsp Freshly Cracked Black Pepper
  • 4 sprigs Fresh Thyme (for roasting)
  • 4 cloves Garlic, lightly smashed
  • 1 Tbsp Unsalted Butter (for searing)
  • 2 Tbsp Unsalted Butter (for sauce)
  • 8 oz Mixed Mushrooms (Cremini, Shiitake, or Oyster), sliced
  • 1 small Shallot, finely minced
  • 2 cloves Garlic, minced (for sauce)
  • 2 Tbsp All-Purpose Flour
  • ½ cup Dry Red Wine (e.g., Pinot Noir or Merlot)
  • 1 cup High-Quality Beef Broth (low sodium)
  • ½ cup Heavy Cream
  • 1 tsp Fresh Thyme leaves, chopped
  • 1 tsp Dijon Mustard
  • Salt and Black Pepper to taste

Instructions:

  1. Prep & Temper: Trim any silver skin from the tenderloin. Pat the roast completely dry with paper towels. Season aggressively on all sides with salt and pepper. Allow the beef to rest at room temperature for at least 1 hour.
  2. Preheat oven to 425°F (220°C).
  3. Sear (Optional but Recommended): Heat olive oil (and butter, if using) in an oven-safe skillet over high heat until shimmering. Sear the tenderloin on all sides until a deep brown crust forms (about 2 minutes per side).
  4. Roast: Place the seared tenderloin in the roasting pan. Tuck the thyme sprigs and smashed garlic cloves around the roast.
  5. Monitor: Roast for 30–45 minutes, checking the internal temperature periodically. Aim for 130°F (54°C) for medium-rare.
  6. Rest: Remove the beef from the oven when it hits the target temperature. Tent loosely with foil and allow it to rest for a crucial 15 minutes (carryover cooking will raise the temp by 5-10 degrees).
  7. Sauté Aromatics: While the beef rests, melt 2 Tbsp butter in a medium saucepan over medium heat. Add sliced mushrooms and cook until deeply browned. Add minced shallot and cook until softened. Add minced garlic and cook for 1 minute.
  8. Make the Roux: Sprinkle the flour over the mushroom mixture. Stir continuously for 1 minute to cook out the raw flour taste.
  9. Deglaze & Simmer: Pour in the red wine (if using) and let it bubble and reduce by half, scraping up browned bits. Whisk in the beef broth slowly until smooth, then bring to a gentle simmer until the sauce thickens slightly.
  10. Finish Sauce: Reduce heat to low. Stir in the heavy cream, Dijon mustard, and fresh thyme. Simmer gently for 2-3 minutes. Taste and adjust seasoning with salt and pepper.
  11. Serving: Slice the rested tenderloin against the grain into thick medallions. Arrange on a platter and spoon the warm mushroom sauce generously over the top.