Best Grilled Flank Steak Recipe Cook’s Illustrated: Juicy Slices With Bold Char Marks

Achieving juicy flank steak with bold char marks requires precision and patience. This method delivers the best results every time, with a perfect crust and tender interior.

I’ve refined this technique through years of grilling, focusing on high heat and proper resting. The secret lies in scoring the meat and using a two-zone fire for even cooking.

What you’ll get is a steak with deep, smoky flavor and a texture that melts in your mouth. The char marks aren’t just for looks—they add layers of complexity.

Serve sliced against the grain for maximum tenderness. This is grilling at its finest.

Ingredients for Best Grilled Flank Steak Recipe Cook’s Illustrated

Simple ingredients transform into a showstopper with bold char marks and juicy tenderness.

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The flank steak is non-negotiable here. Look for 1-inch thickness—any thinner overcooks fast. Whole Foods or Costco have great options, but most butcher counters can cut to order. Scoring the surface (crosshatch cuts) lets the marinade penetrate deep. Diamond Crystal salt is my go-to for even seasoning, but any kosher salt works if that’s what you’ve got.

No soy sauce? Worcestershire plus a pinch of salt gets you close (just check for anchovies if that’s a concern). Fresh out of cilantro? Flat-leaf parsley works in a pinch. The lime juice can be bottled (in a pinch), but fresh makes a noticeable difference. Want more heat? Keep the jalapeño seeds or add a dash of cayenne.

Marinate the steak for 2-12 hours—don’t go longer or the texture gets mealy. Leftovers slice beautifully for tacos and keep 4-5 days in the fridge. Freezes well too, up to 3 months if wrapped tight.

Step-by-Step Instructions for Grilled Flank Steak

Here’s the method that delivers juicy, char-marked perfection every single time.

Step 1: Create the Flavor-Packed Marinade

In a mixing bowl, whisk together 0.25 cup olive oil, 0.25 cup soy sauce, 2 tbsp lime juice, 1 tbsp brown sugar, 4 cloves garlic cloves (minced into paste), 1 whole jalapeño (seeds removed, minced), 1 tsp ground cumin, and 1 tsp smoked paprika until the brown sugar fully dissolves.

This combination creates a bold, tangy-sweet base that tenderizes the flank steak while adding layers of flavor. I always let the marinade sit for 5 minutes before using to allow the spices to bloom fully in the liquid.

Step 2: Marinate and Prep the Steak

Place the 2 lb flank steak in a resealable plastic bag or shallow dish and pour the marinade over it. Turn to coat completely, then sprinkle both sides evenly with 2 tsp kosher salt and 1 tsp black pepper. Press the seasoning into the meat gently to help it adhere.

Seal the bag or cover the dish and refrigerate for at least 4 hours, or ideally overnight. For best results, flip the steak halfway through marinating. The longer it sits, the more tender and flavorful it becomes. Remove from the fridge 30 minutes before grilling to bring it closer to room temperature.

Step 3: Grill Over High Heat for Char Marks

Preheat your grill to high heat (about 450-500°F) and clean the grates thoroughly. Remove the flank steak from the marinade (discard the marinade) and pat it dry with paper towels. This step is crucial—wet meat won’t sear properly.

Place the steak on the hot grill and cook for 4-5 minutes per side for medium-rare, or until a meat thermometer inserted into the thickest part reads 130-135°F. Don’t move it around—let it develop those beautiful char marks before flipping once. The steak should release easily when it’s ready to turn.

Step 4: Rest and Slice Against the Grain

Transfer the grilled flank steak to a cutting board and let it rest for 10 minutes. This allows the juices to redistribute throughout the meat. Tent it loosely with foil to keep it warm.

Locate the grain direction (you’ll see lines running through the meat) and slice thinly against the grain at a slight angle. This shortens the muscle fibers, making each bite incredibly tender. Garnish with 0.25 cup fresh cilantro before serving. The slices should be juicy with perfect grill marks on each piece.

Creative Variations of These Flavors

Asian-Inspired Twist

Swap the marinade for a bold Asian profile: ⅓ cup soy sauce, 2 tbsp rice vinegar, 1 tbsp honey, 1 tbsp grated ginger, and 2 minced garlic cloves. I love how this version pairs with jasmine rice and quick-pickled veggies. Foraging wild ginger adds an earthy depth I adore.

Coffee-Rubbed Boldness

Create a dry rub with 2 tbsp finely ground coffee, 1 tbsp brown sugar, 1 tsp smoked paprika, and 1 tsp kosher salt. Pat the steak dry, coat with 1 tbsp olive oil, then press on the rub. Grill as usual—the coffee adds a deep, complex char. 🔥

Citrus-Herb Marinade

Combine ¼ cup olive oil, zest and juice of 1 orange, 2 tbsp lime juice, 3 tbsp chopped cilantro, and 2 minced garlic cloves. This bright version is perfect for summer cookouts. I often add a pinch of wild oregano I’ve foraged along the coast.

Spicy Chipotle Lime

Blend ¼ cup olive oil, 2 tbsp lime juice, 1 tbsp adobo sauce (from canned chipotles), 1 minced chipotle pepper, and 1 tsp ground cumin. The smoky heat complements the steak’s richness. Serve with avocado slices to cool the palate.

Mediterranean Herb Crust

Mix ¼ cup olive oil, 2 tbsp lemon juice, 1 tbsp chopped rosemary, and 1 tbsp chopped thyme. Press this mixture onto the steak before grilling. The herbs create an aromatic crust that’s irresistible. Honestly, this one reminds me of my French training days.

Frequently Asked Questions