Ingredients:

  • 2 beef tenderloin steaks (medallions), about 1-1.5 inches (2.5-3.8 cm) thick, roughly 6 oz (170g) each
  • 1 tablespoon olive oil (15 ml)
  • 1 tablespoon unsalted butter (14g)
  • 1/2 teaspoon kosher salt (3g)
  • 1/4 teaspoon black pepper (1g)
  • 1 clove garlic, minced
  • 1 sprig fresh rosemary (optional)
  • 1/2 cup dry red wine (e.g., Merlot, Cabernet Sauvignon) (120ml)
  • 1/4 cup beef broth (60ml)
  • 1 tablespoon balsamic vinegar (15ml)
  • 1 teaspoon brown sugar (4g)
  • 1/2 teaspoon Dijon mustard (3g)
  • 1 tablespoon unsalted butter, cold (14g)

Instructions:

  1. Pat the beef medallions dry with paper towels. Season generously with salt and pepper.
  2. Heat olive oil and butter in a cast iron skillet over medium-high heat until shimmering. Add minced garlic and rosemary to the skillet (if using). Sear the beef medallions for 3-4 minutes per side for medium-rare, adjusting time for desired doneness.
  3. Use a meat thermometer to ensure the internal temperature reaches the desired level (e.g., 130-135°F (54-57°C) for medium-rare).
  4. Remove the medallions from the skillet and place them on a plate. Cover loosely with foil and let rest for at least 5 minutes.
  5. In the same skillet (without wiping it out), pour in the red wine. Scrape up any browned bits from the bottom of the pan.
  6. Add beef broth, balsamic vinegar, brown sugar, and Dijon mustard. Bring to a simmer over medium heat and cook until the sauce has reduced by about half and thickened slightly, about 5-7 minutes.
  7. Remove from heat and whisk in the cold butter until melted and emulsified.
  8. Spoon the red wine reduction over the rested beef medallions and serve immediately.