- 1.5 – 2 lbs (680-900g) flank steak
- The star: Look for one with long, visible grain and minimal sinew.
- 3-4 large cloves garlic, finely minced or grated
- 2 tablespoons fresh rosemary, finely chopped
- Zest of 1 lemon (save the juice!)
- 1 teaspoon coarse sea salt or kosher salt
- ½ teaspoon freshly cracked black pepper
- ¼ teaspoon red pepper flakes (optional, for a touch of heat)
- ⅓ cup (80ml) extra-virgin olive oil, plus more for cooking
For the Finishing Sauce:
- Juice of the zested lemon
- 2 tablespoons extra-virgin olive oil
- 2 tablespoons finely chopped fresh parsley
- Flaky sea salt, for finishing
The Method: Marinate, Sear, Rest, Slice
The process is simple, but timing is everything for maximum tenderness.
Step 1: The Flavor Infusion (Marinate).
Pat the flank steak completely dry with paper towels. In a small bowl, make the marinade paste: combine the garlic, rosemary, lemon zest, salt, pepper, red pepper flakes, and ⅓ cup olive oil. Rub this paste all over the steak, coating it thoroughly. Place it in a dish or a zip-top bag and let it marinate in the refrigerator for at least 2 hours, and up to 12 hours (overnight is ideal).
Step 2: The Sear (Hot & Fast).
An hour before cooking, take the steak out of the fridge to come to room temperature. Scrape off most of the marinade paste (it can burn).
Heat a heavy skillet (cast-iron is perfect) or grill over high heat until smoking hot. Add a thin film of oil. Sear the steak undisturbed for 5-7 minutes per side for medium-rare (135°F internal temperature), or until your desired doneness. Flank steak is best served medium-rare to medium—any more and it can become tough.
Step 3: The Crucial Rest.
Transfer the steak to a cutting board and let it rest, tented loosely with foil, for 10 full minutes. This allows the juices to redistribute, ensuring every slice is moist.
Step 4: The Finale (Slice & Sauce).
This is the most important step: Identify the direction of the grain (the long muscle fibers). Using a very sharp knife, slice the steak across the grain into thin, ¼-inch strips. This cuts the fibers short, guaranteeing tenderness.
Arrange the slices on a platter. Whisk together the lemon juice, 2 tbsp olive oil, and parsley. Drizzle this bright, fresh sauce over the warm meat. Finish with a sprinkle of flaky sea salt.
Chef’s Secrets for the Perfect Steak
- The Cross-Grain Rule: Slicing against the grain is non-negotiable for flank steak. It transforms a potentially chewy cut into a tender one.
- Don’t Skip the Rest: Rushing this step means juicy steak ends up on your cutting board, not on your plate.
- The Garlic Guardian: Minced garlic can burn in a hot pan. Scraping off the bulk of the marinade before searing prevents bitterness.
- Carryover Cooking: The steak’s internal temperature will rise 5-10°F while resting. Pull it off the heat at 130°F for a perfect medium-rare.
