Grilled Balsamic and Garlic Flank Steak Recipe

There are few culinary experiences as satisfying as slicing into a perfectly grilled steak—charred on the outside, juicy on the inside, and bursting with bold, complex flavors. But steak doesn’t have to be an expensive ribeye or a labor-intensive porterhouse to deliver that kind of satisfaction. Enter the flank steak: a lean, flavorful, and affordable cut of beef that, when handled properly, can rival any premium steakhouse meal.

This recipe for Grilled Balsamic and Garlic Flank Steak is all about elevating a humble cut with smart techniques and simple, high-impact ingredients. Balsamic vinegar provides tang and subtle sweetness, garlic brings aromatic intensity, and a blend of fresh herbs and oil tenderizes and seasons the meat from the inside out. With a quick marinade and a hot grill, you can achieve a steak that’s deeply savory, slightly sweet, and full of juicy, meaty character.

Flank steak is particularly well-suited to marinades. Its open grain and relatively thin profile allow it to absorb flavor quickly, and when grilled over high heat and sliced against the grain, it becomes incredibly tender. This dish is ideal for backyard cookouts, weeknight dinners, or special occasions when you want to impress without stress.

But this recipe goes beyond just flavor—it’s about confidence and technique. We’ll walk you through the entire process, from selecting and prepping the meat to grilling it to perfection, slicing it properly, and pairing it with sides. You’ll learn not just how to cook this recipe, but why each step matters.

Whether you’re a grilling novice or a seasoned backyard pitmaster, this guide will help you master one of the most rewarding—and underrated—steak recipes out there. All you need is a quality cut of beef, a few pantry staples, and a hot grill.

Now let’s dive into the process and walk step-by-step through the preparation of this irresistible grilled flank steak.

Step-by-Step Instructions

Ingredients:

For the Steak and Marinade:

• 1½ to 2 pounds flank steak

• ¼ cup balsamic vinegar (aged or traditional)

• 3 tablespoons olive oil (extra virgin preferred)

• 4 garlic cloves, finely minced or crushed

• 1 tablespoon soy sauce (for umami depth)

• 1 tablespoon honey or brown sugar (balances acidity)

• 1 teaspoon Dijon mustard (optional, for bite)

• ½ teaspoon freshly ground black pepper

• ½ teaspoon kosher salt

• 1 tablespoon chopped fresh rosemary or thyme (or 1 tsp dried)

For Finishing:

• Flaky sea salt, for serving

• Fresh chopped parsley, rosemary, or thyme

• Optional: squeeze of lemon juice or drizzle of extra balsamic for brightness

Step 1: Prepare the Marinade

1. Combine all marinade ingredients in a mixing bowl or resealable bag:

   • Balsamic vinegar

   • Olive oil

   • Garlic

   • Soy sauce

   • Honey or brown sugar

   • Dijon mustard (if using)

   • Black pepper

   • Salt

   • Herbs

2. Whisk until well blended. The oil and vinegar should emulsify slightly, and the aromatics should be evenly distributed.

Why it matters: The acidity of the balsamic vinegar tenderizes the meat, while the oil and soy sauce provide richness and depth. Garlic and herbs infuse aroma into the fibers of the flank steak.

Step 2: Marinate the Flank Steak

1. Place the steak in a large zip-top bag or shallow glass container.

2. Pour the marinade over the steak, ensuring it’s evenly coated on all sides.

3. Seal and refrigerate for at least 2 hours, or up to 12 hours.

   • If short on time, even 30–60 minutes will make a noticeable difference.

Pro Tip: Turn the steak once or twice during marinating to ensure even flavor absorption.

Step 3: Preheat the Grill

1. Preheat a gas or charcoal grill to high heat. You want the grates very hot—at least 450°F to 500°F—to create a good sear.

2. Clean and oil the grates just before cooking to prevent sticking.

Alternative: You can also cook this steak indoors using a grill pan or cast iron skillet. Preheat until the surface is lightly smoking.

Step 4: Remove and Pat Dry the Steak

1. Remove steak from the marinade and let excess liquid drip off.

2. Pat the surface dry with paper towels. This helps develop a better sear.

3. Let the steak sit at room temperature for about 20 minutes before grilling (if it’s been chilled for several hours).

Why this matters: A dry surface and room-temp meat mean better browning and more even cooking.

Step 5: Grill the Flank Steak

1. Place the steak on the grill over direct heat.

2. Grill for 4–6 minutes per side, depending on thickness and desired doneness:

   • Medium-rare: 125–130°F

   • Medium: 135°F

   • Medium-well: 145°F (not recommended—flank can become tough)

3. Use a meat thermometer for accuracy. Insert it into the thickest part of the steak.

4. Once done, transfer to a clean cutting board and tent loosely with foil.

Tip: Don’t overcook. Flank steak is lean and benefits from a pink center to remain tender.

Step 6: Rest the Steak

Let the steak rest for 5–10 minutes before slicing.

Why it matters: Resting allows the juices to redistribute throughout the meat, keeping it moist when sliced.

Step 7: Slice the Steak (Correctly!)

1. Identify the grain—the direction the muscle fibers run.

2. Slice against the grain (perpendicular to the lines) into thin strips.

   • This shortens the muscle fibers and makes each bite more tender.

Optional: Sprinkle with flaky sea salt, fresh herbs, or a final drizzle of balsamic reduction.

Step 8: Serve and Pair

Serve warm, accompanied by:

• Roasted vegetables (asparagus, bell peppers, mushrooms)

• Garlic mashed potatoes or grilled corn

• Arugula salad with lemon vinaigrette

• Crusty artisan bread or couscous