Ingredients & Substitutions
Here I explain the best ingredients for grilling London broil, what each one does in my recipe, and substitution options. For measurements, see the recipe card.
Flank Steak – London broil was originally made with flank steak, and that’s what I used here. But these days, the name is more about the cooking method than the cut of meat. You might see butchers label top round steak, Coulotte, or other cuts as London broil, and those work great, too. Oil – I use olive oil to lock in moisture. Avocado oil makes a good substitute. Balsamic Vinegar – This key ingredient tenderizes the meat. My other version uses lemon juice for this purpose and you certainly can use it for grilled London broil, too, but this time I opted for balsamic. Apple cider vinegar or red wine vinegar would achieve a similar effect, with a different flavor. Coconut Aminos – This adds flavor and balances the acidic vinegar. Low sodium soy sauce is fine to substitute, but I prefer aminos because I limit soy — plus it adds a nice hint of sweetness. Worcestershire Sauce – For umami flavor and a hint of sweetness in the grilled London broil marinade! I like this brand, which is gluten-free. If you don’t have any, you can just increase the coconut aminos, but nothing beats the original. Garlic – When I’m in a rush, I’ll sometimes use the a tablespoon of the jarred stuff, but let’s be real, nothing beats fresh garlic. Fresh Herbs – Fresh rosemary and thyme pair best with this cut. I’ve also made this recipe using 1 teaspoon each of dried herbs instead of 1 tablespoon each of fresh. Or use 2 teaspoons of my Italian seasoning. Spices – Sea salt, black pepper, and crushed red pepper flakes for flavor and heat.
How To Cook London Broil On The Grill
I have step-by-step photos here to help you visualize the recipe. For full instructions with amounts and temperatures, see the recipe card.
How Long To Grill London Broil?
London broil grill time depends on how you like it cooked. Most of my family likes it medium-rare, so I cook it for 2 minutes per side on high heat, followed by 9-10 minutes at lower heat. If you prefer it more or less done, check out my time chart below. *Note: These grill times are based on a 1 inch thick steak, and the temperature is when you’d remove it from the grill. The internal temp will rise another 5 degrees while resting.
Marinade Variations
Grilled London broil definitely needs a good marinade, even if you don’t use the one I did. I always include oil for richness, plus something acidic (like vinegar) and salt to tenderize. Try one of these if you want some different flavors:
Marinate for as long as you can, but not over 24 hours. My bare minimum is 2-3 hours, but it’s even better closer to the 24 hour mark. Just don’t go over, or it starts to taste mushy. Bring the steak to room temperature before grilling. I always let it sit out for about 30 minutes. This helps it cook more evenly and leaves it more juicy. Let any extra marinade drip off before placing the London broil on the grill. Extra oil dripping down can cause flare-ups, so be careful! Use a meat thermometer to nail the perfect doneness. Grilling London broil for too long can make it tough, so aim for medium-rare to medium doneness. My time chart above is a good starting point, but go by the internal temp if you can — times can vary depending on exactly how hot your grill gets and how long you keep the lid open (to add the steak and flip it). I like to use my probe thermometer, so that I don’t have to open the lid to check. Slice thinly against the grain. This breaks up the muscle fibers, making every bite super tender. Just look at which way the grains run and cut in the opposite direction.
Chimichurri – Whip up my chimichurri sauce and use 1 cup per pound of steak. Montreal – Swap the herbs and spices above for 1 teaspoon of my Montreal steak seasoning. Fajita – Use my sheet pan fajita recipe (with oil, lime juice, and fajita seasoning) and marinate the steak instead of cooking it right away. So good! Teriyaki – For a sweet and savory vibe, I marinate in teriyaki sauce, with a little extra minced garlic and ginger. Garlic Lime – Check out my flank steak tutorial and use the lime marinade from there.
Storage & Meal Prep
Store: Keep leftovers in an airtight container in the refrigerator. They’ll stay good for 3-5 days. I like to repurpose them in my steak salad for a quick and easy lunch. Meal prep: This recipe is perfect for meal prep the day before, since you can marinate it for up to 24 hours. Sometimes I mix up the marinade several days ahead and just add the steak the day before. Reheat: You can reheat your London broil on the grill again over indirect heat, or pop it in the oven for about 10 minutes.
Serving Suggestions
Grilled London broil calls for some summery sides! Here are some of my tasty favorites:
Grilled Vegetables – My faves in the summer are grilled eggplant or grilled zucchini, although this time I made grilled cauliflower (pictured above). But if you want a veggie that pairs incredibly with the flavors in this grilled London broil recipe, make my balsamic brussels sprouts. Potatoes – You can grill them, but I like to roast potatoes in the air fryer while I’m grilling the steak. It’s just less fuss. Salad – I love a grilled peach salad or strawberry spinach salad for those summery vibes.
Please enter your first name for your account. Your saved recipe will also be sent to your email. Nutrition info uses half of the marinade, as at least half is discarded.
