Succulent Blackstone London Broil

If you ask me, London broil cooked on a Blackstone griddle is one of the smartest ways to cook this cut of beef.

This tried-and-true steak dinner brings together the rich taste of marinated beef with the perfect char you can only get from cooking on a flat top. The meat comes out nicely browned on the outside while staying pink and juicy in the middle.

The high heat of the Blackstone gives you those nice grill marks and caramelized bits that add so much flavor. A simple marinade with garlic and herbs helps tenderize the meat and adds just the right seasoning.

It’s a no-fuss meal that’s perfect for feeding a hungry family, and the leftovers make amazing sandwiches the next day.

What Kind of Steak Should I Use?

London broil isn’t actually a cut of meat – it’s a cooking method that works great with several different beef cuts. The most common choices are top round steak, flank steak, or skirt steak, and each brings something different to the table. Top round is usually the most budget-friendly option and has a lean, firm texture that’s great for slicing thin. Flank steak has more intense beef flavor and a noticeable grain that you’ll want to cut against for the most tender results. If you’re going with skirt steak, you’ll get the richest, beefiest flavor of the three, though it’s typically the priciest option. Just remember that whichever cut you choose, letting it rest for about 10 minutes after cooking and slicing against the grain will give you the most tender results.

Options for Substitutions

This recipe is pretty flexible and you can make several swaps if needed:

• London broil cut: While the recipe calls for London broil, you can use any of these cuts: flank steak, skirt steak, or top round steak. Just remember that cooking times might vary slightly depending on the thickness of your cut.
• Soy sauce: If you need a gluten-free option or are out of soy sauce, try coconut aminos or tamari. You can also use Worcestershire sauce mixed with a bit of water, though the flavor will be slightly different.
• Balsamic vinegar: Red wine vinegar or apple cider vinegar can work in place of balsamic. If using these substitutes, add 1 teaspoon of honey or brown sugar to make up for balsamic’s natural sweetness.
• Extra virgin olive oil: Any neutral cooking oil like avocado oil or vegetable oil will work fine here. Just avoid oils with low smoke points since this is a high-heat cooking method.
• Fresh garlic: If you’re out of fresh garlic, you can use 1 teaspoon of garlic powder instead of the 3 cloves. In a pinch, 1½ teaspoons of pre-minced garlic from a jar will also do the job.
• Parsley garnish: Feel free to skip the parsley or swap it with fresh cilantro or chives – it’s mainly for adding a pop of color and fresh flavor at the end.

Watch Out for These Mistakes While Grilling

The biggest mistake when cooking London broil on a Blackstone is not letting the meat come to room temperature before grilling – take it out of the fridge at least 30 minutes beforehand to ensure even cooking from edge to center. Another common error is slicing the meat with the grain instead of against it, which can make even a perfectly cooked London broil tough and chewy – always cut across the grain at a 45-degree angle for the most tender results. The timing of your flip is crucial too – resist the urge to constantly turn the meat and instead let it develop a nice crust on each side, about 5-7 minutes per side for medium-rare, depending on thickness. For the juiciest results, let the meat rest for 10-15 minutes after cooking, as cutting into it too soon will cause all those flavorful juices to run out onto your cutting board instead of staying in the meat.

What to Serve With London Broil?

This juicy grilled London broil calls for some classic steakhouse-style sides to round out your meal. A baked potato loaded with butter and sour cream or crispy roasted potatoes make perfect partners for the meat. Since London broil has such a rich flavor, I like to balance it with something green – sautéed asparagus, roasted broccoli, or a simple garden salad all work great. For a complete meal, you might want to add some sautéed mushrooms and onions on top of the steak, which complement the meat’s savory taste. And don’t forget some crusty bread on the side to soak up any extra juices and cowboy butter!

Storage Instructions

Keep Fresh: Got leftover London broil? Place it in an airtight container and pop it in the fridge for up to 3 days. Pro tip: slice it only when you’re ready to eat to help keep the meat juicy. If you’ve already sliced it, no worries – just store the slices in their own juices to maintain moisture.

Freeze: This London broil freezes really well for future meals. Wrap it tightly in plastic wrap, then aluminum foil, or place it in a freezer bag with the air squeezed out. It’ll keep its quality for up to 3 months in the freezer. Just remember to label it with the date!

Reheat: To keep your London broil tender when reheating, warm it gently in a skillet over medium-low heat with a splash of beef broth or butter. You can also wrap it in foil and heat in the oven at 250°F for about 20 minutes. Try to avoid the microwave if possible, as it can make the meat tough.

Preparation Time	15-30 minutes
Cooking Time	20-30 minutes
Total Time	2 hours 35 minutes – 3 hours
Level of Difficulty	Medium

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 2200-2400
• Protein: 150-160 g
• Fat: 160-170 g
• Carbohydrates: 20-25 g

Ingredients

For the steak:

• 2 lb London broil (1.5 to 2 inches thick for even cooking)
• 3 garlic cloves (minced finely)
• 1/2 tsp kosher salt
• 1/4 cup soy sauce (I use Kikkoman)
• 1/4 cup olive oil (extra virgin for better flavor)
• 1 tsp paprika (smoked paprika preferred)
• 1 tbsp olive oil (for cooking on Blackstone)
• 1/2 tsp black pepper (freshly ground)
• 1/4 cup balsamic vinegar (aged adds depth)

For serving:

• chopped parsley (fresh, for garnish)
• cowboy butter (compound butter with herbs and garlic)

Step 1: Prepare the Marinade and Begin Marinating

• 3 garlic cloves, minced finely
• 1/4 cup soy sauce
• 1/4 cup olive oil
• 1/4 cup balsamic vinegar
• 1 tsp paprika
• 1/2 tsp kosher salt
• 1/2 tsp black pepper, freshly ground
• 2 lb London broil

While this recipe calls for marinating in a bag, I prefer to marinate in a shallow dish where I can easily turn the meat and ensure even coverage.

Whisk together the minced garlic, soy sauce, olive oil, balsamic vinegar, paprika, kosher salt, and freshly ground black pepper in a small bowl until well combined.

Place the London broil in a shallow container or zip-top bag and pour the marinade over it, making sure all surfaces are coated.

Cover and refrigerate for at least 2 hours, though overnight is ideal for deeper flavor development.

The acid in the balsamic and soy sauce will begin breaking down the muscle fibers, making the meat more tender.

Step 2: Bring Meat to Room Temperature and Set Up Cooking Station

• 2 lb London broil from Step 1

Remove the London broil from the refrigerator 30 minutes before cooking—this allows the meat to cook more evenly by bringing the interior closer to the target temperature.

While the meat comes to temperature, preheat your Blackstone griddle to high heat (around 450-500°F) and place an oven rack in the middle position.

Have all your tools ready: tongs for flipping, a meat thermometer for checking doneness, and a clean cutting board for resting the finished steak.

Step 3: Sear the Steak on the Blackstone

• 2 lb London broil from Step 1
• 1 tbsp olive oil

Pat the marinated London broil dry with paper towels—this removes excess moisture and allows for better browning and crust development.

Drizzle the 1 tablespoon of olive oil across the preheated Blackstone griddle, letting it shimmer and just begin to smoke.

Carefully place the steak on the griddle and sear without moving it for 1-2 minutes per side until you develop a deep golden-brown crust.

I like to sear the meat on the hottest part of the Blackstone where it makes contact with the surface, which creates that beautiful caramelized exterior that locks in juices.

Step 4: Finish Cooking to Medium-Rare

• seared London broil from Step 3

After searing, move the steak to a slightly cooler zone of the Blackstone (medium-high heat, around 350°F) or reduce the heat if your griddle has adjustable burners.

Continue cooking, flipping halfway through, until the internal temperature reaches 135°F for medium-rare, which typically takes 8-10 additional minutes depending on thickness and griddle temperature.

Check the temperature with a meat thermometer inserted into the thickest part of the meat without touching the griddle surface.

Remember that the steak will continue to cook slightly during resting, so pulling it at 135°F ensures it won’t be overdone.

Step 5: Rest and Slice the Steak

• cooked London broil from Step 4

Transfer the cooked steak to a clean cutting board and let it rest for 10 minutes—this allows the muscle fibers to relax and reabsorb the juices, keeping each slice moist and tender.

While the meat rests, you can prepare any finishing elements.

After resting, slice the London broil against the grain into strips about 1/4-inch thick, which breaks up the muscle fibers and makes the meat more tender to eat.

Step 6: Plate and Garnish

• sliced London broil from Step 5
• cowboy butter
• chopped parsley

Arrange the sliced steak on a serving platter.

Top with a generous pat of cowboy butter, allowing it to melt over the warm meat and create a luxurious sauce.

Finish with fresh chopped parsley for color and a bright herbal note that cuts through the richness of the butter and meat.