London broil is traditionally prepared by broiling or grilling marinated top round steak or flank steak, then cutting it into thin strips. The beef cuts used for London broil are very lean and very flavorful, but they can easily become tough, hence the importance of marinating, of of cooking to medium-rare (130 degrees F), and of slicing very thinly.
I like to keep things simple by purchasing a not-too-thick top round steak (1 inch is good), marinating it for a few hours, then pan-frying in a cast-iron skillet. It’s a simple recipe that highlights the bold, beefy flavor of top round steak and requires very little work.
- 2 tablespoons balsamic vinegar
- 2 tablespoons soy sauce
- 1 tablespoon Dijon mustard
- 1 teaspoon garlic powder
- 1 teaspoon ground cumin
- 1.5 lbs. top round steak, 1 - 1.25 inches thick
- 1 teaspoon kosher salt
- ¼ teaspoon black pepper
- 1 teaspoon refined coconut oil
- In a small bowl, whisk together the balsamic vinegar, soy sauce, mustard, garlic powder and cumin. Place the steak in a ziploc bag. Pour the marinade into the bag and rub all over the steak. Seal the bag, removing as much air as possible. Place the bag in the fridge for 4 hours or overnight. (I usually do this in the morning, and the steak is ready for me to fry at dinnertime). If you're home while the steak is marinating, flip it once in a while.
- Remove the steak from the fridge 2 hours (but no more than that) before cooking, to allow it to reach room temperature.
- Heat a cast iron skillet over medium-high heat until very hot, about 3 minutes. It's important to use cast iron in this recipe, because the final stage of cooking relies on the skillet's ability to retain heat.
- Remove the steak from the bag and pat dry with paper towels. Sprinkle with salt and pepper. Add the coconut oil to the skillet and brush to coat. Place the steak in the hot skillet. Cook it 3 minutes, without moving. Flip to the other side (it should be deeply browned and slightly charred on the first side) and cook 3 more minutes, again without moving it.
- Using oven mitts, remove the skillet from the heat. Tent it with foil, and allow the steak to rest - and finish cooking from the skillet's heat - for 5 minutes. (The best way to ensure that the steak is done to your liking is using an instant-read thermometer. Medium-rare is 130-135 degrees F, medium is 140-145 degrees F.)
- Transfer the London Broil to a cutting board. Slice it very thinly, and serve.
Consuming raw or undercooked meats, poultry, seafood, shellfish or eggs may increase your risk of foodborne illness.