Ingredients:
- 5 lbs Beef Sirloin, Flank, or Tri-Tip (cut into 1–1.5 inch cubes)
- 2 Tbsp Extra Virgin Olive Oil
- 3 Tbsp Low-Sodium Soy Sauce
- 2 Tbsp Worcestershire Sauce
- 1 tsp Dijon Mustard
- 1 tsp Garlic Powder
- 1 tsp Freshly Ground Black Pepper
- Kosher Salt, as needed
- 4 Tbsp Unsalted Butter, cold, cut into 4 cubes/pats
- 1 medium Shallot, finely minced (or 2 Tbsp Onion)
- 3 cloves Fresh Garlic, minced
- 1 tsp Fresh Thyme Leaves
- ½ tsp Chopped Fresh Rosemary
- ¼ cup Beef Stock (or Red Wine)
Instructions:
- Trim any large pieces of silver skin or excess fat from the beef. Cut the steak into roughly equal 1 to 1.5-inch cubes. Consistency is key for even cooking.
- In a bowl or Ziplock bag, combine the steak tips, 2 tablespoons olive oil, soy sauce, Worcestershire, Dijon, garlic powder, and black pepper. Toss well to coat every piece.
- Marinate in the refrigerator for a minimum of 1 hour, or up to 4 hours.
- Remove the steak tips from the marinade and place them on a paper towel-lined tray. Pat them aggressively dry. Sprinkle the dried tips liberally with Kosher salt just before cooking.
- Place the cast iron skillet over high heat. Add 1 tablespoon of olive oil (or neutral oil like grapeseed). Wait until the oil is shimmering and just beginning to smoke.
- Place half of the steak tips into the hot pan, ensuring there is space between each piece. Sear undisturbed for 2–3 minutes until a deep brown crust forms on the bottom side.
- Turn the pieces with tongs and continue cooking, flipping occasionally, until the desired internal temperature is reached (130–135°F for Medium-Rare).
- Transfer the cooked steak tips immediately to a clean cutting board or warm plate. Cover loosely with foil and rest for 5–7 minutes.
- Reduce the heat to medium. Add the minced shallots to the skillet (if necessary, wipe out any burnt bits first, but leave the brown 'fond'). Sauté for 1 minute until soft.
- Add the minced garlic, thyme, and rosemary. Cook for 30–60 seconds until fragrant—do not let the garlic burn!
- Pour in the beef stock and scrape up all the brown bits (fond) stuck to the bottom of the pan. Let the liquid reduce by half.
- Remove the pan from the heat. Add the cold cubes of unsalted butter one at a time, whisking constantly until a rich, emulsified sauce forms.
- Add the rested steak tips (and any accumulated resting juices) back into the pan. Toss gently to coat them thoroughly in the butter sauce. Serve immediately.