Essential Guide: How Long to Cook London Broil on Grill

Many face the same challenge with London broil: either too rare or overcooked - mastering the right grilling time is the solution.

How long does it take to cook London broil on grill?

When grilling thick - cut beef like London Broil, it usually takes 12 - 18 minutes to cook the whole piece of meat. The specific time is still related to some factors.

Thickness determines the basic cooking time

For a 2.5 - centimeter - thick piece of meat, first sear each side over high heat for 4 minutes to form a charred crust, then move it to the indirect - heat area and roast for 5 minutes. The center will reach medium - rare doneness. If the meat is cut 4 centimeters thick, the direct - heat roasting time needs to be extended to 6 minutes per side, and the total cooking time is about 20 minutes.

Correspondence between temperature and doneness

Preheat the grill to a high temperature of 230°C. Insert a meat thermometer into the thickest part of the meat: 54°C indicates rare doneness, 58°C indicates medium - rare doneness, and 63°C indicates medium - well doneness. The key is to take the temperature every 30 seconds in the last five minutes to avoid overcooking and making the meat tough.

Techniques for locking in juice and turning the meat

Don't turn the meat frequently! I usually only turn it three times throughout the process: After searing each side for 2 minutes initially, start timing when turning it for the third time. After cooking, immediately wrap it in aluminum foil and let it rest for 8 minutes. During this period, the temperature will continue to rise by 3 - 5°C, and the meat will be more tender and juicy.

Do you grill London broil with the lid open or closed?

The lid must be open during the high - heat sear stage:

Keep the grill completely open for the first 3 minutes to let the flames directly contact the steak. Grill each side for 90 seconds. High heat can quickly form a caramelized layer. Steaks grilled with the lid open at this stage have a surface crispness increase of over 40%, and there is actually less juice loss.

The lid must be closed during the crucial slow - cooking stage:

Close the lid immediately after getting the cross - hatch marks and turn the heat down to medium. At this time, a circulating hot air forms inside. For a thick - cut 3 - centimeter piece of meat, it needs to be grilled with the lid closed for about 8 minutes, and only flip it once during this period. With the lid closed, the internal temperature is more stable, preventing the outer layer from being over - cooked while the inside remains under - cooked.

What to season London broil with?

Classic black pepper and whiskey base flavor

Season with coarse sea salt and freshly ground black pepper as the base, sprinkle 1/4 teaspoon on each side. Before grilling, brush on a sauce made from bourbon whiskey and brown sugar (ratio 2:1). The high heat will make the alcohol evaporate, leaving behind a smoky and sweet aroma. This combination is especially suitable for thick - cut meat pieces over 4 centimeters.

Mediterranean herb trio

Mix 1 teaspoon each of dried rosemary, thyme and oregano, and make a paste with garlic and olive oil. Spread it on the meat 2 hours in advance and refrigerate. The herbs will form a crispy crust during grilling. Note not to apply too thick a layer of the spice mixture, otherwise it may easily burn and turn bitter.

Quick Asian - style marinating method

Make a sauce by mixing light soy sauce, rice vinegar and sesame oil in a ratio of 3:1:1, and dilute it with half a teaspoon of honey. Make shallow incisions on the steak and soak it for 20 minutes, then pat dry the surface before grilling. This marinade can make the meat more tender, and the grilled crust will have a faint caramel aroma.

I particularly recommend seasoning during the resting stage: Immediately sprinkle lemon zest or smoked paprika after grilling. The residual heat will enhance the aroma without ruining the crust. For parts with connective tissue, you can brush a layer of pineapple juice in the last 2 minutes of grilling. The natural enzymes can soften the connective tissue.

Should London Broil rest after grilling?

After grilling, London Broil definitely needs to rest. These few minutes directly affect the success of the meat texture.

Calculate the resting time according to the thickness

For every centimeter of thickness, the resting time is 5 minutes. For example, a 3 - centimeter - thick piece of meat needs to rest for 15 minutes. In actual operation, there's no need for precise measurement. Just let the meat rest for 8 - 10 minutes after grilling.

There are special ways to let it rest

Don't place it directly on the cutting board! I usually put a pre - heated plate under the grill rack, so that the meat can be suspended in the air and ventilated.

If the conditions are limited, at least prop the meat up with two chopsticks to prevent the bottom from getting soggy due to steam. The optimal temperature during this period is between 50 - 60 °C. You can loosely cover the surface with aluminum foil.

What's the best way to slice grilled London Broil?

It is best to slice it against the grain and at an angle, as the angle determines the tenderness.

Lay the rested steak flat. First, find the direction of the muscle fibers - they are like parallel straws. When cutting, the knife must be perpendicular to these fibers, forming a 90 - degree angle to break the fibers.

If the fibers run horizontally, you should cut vertically. If the fibers are at an oblique angle, adjust the knife to cut at an angle of about 60 degrees.

A serrated knife is more practical than a smooth - bladed knife, especially when dealing with the crispy surface layer of the meat. Control the thickness of each slice to be about 0.5 centimeters. If the slices are too thin, they are likely to fall apart, and if they are too thick, they are difficult to chew.

There is a way to check: Stand the sliced meat upright and gently shake it. If it bends naturally but does not break, it means the thickness is just right.

Here are two common mistakes to avoid:

Don't saw back and forth like cutting bread. Instead, press down smoothly like opening an envelope.

Plate the slices immediately after cutting. Long exposure will make the cut surface dry out.

Is it better to grill or broil London broil?

It actually depends on personal preference, but I prefer the broiling method. The reason is that its high temperature can quickly seal in the meat juices, and it is suitable for thicker cuts of meat. No matter which method you choose, mastering the skills is the most crucial.

London broil has a relatively tough texture, so marinating it in advance is very important. I usually make a sauce with red wine, olive oil, garlic, and black pepper and marinate the meat in the refrigerator for at least 4 hours. This can both soften the fibers and add flavor.

If using the broiling mode, remember to place the meat about 10 centimeters away from the upper heat source. Broil each side for 4 - 5 minutes under high temperature. Take the meat out immediately when it is medium - rare, let it rest for 5 minutes before slicing. If using an open - flame grill, it is recommended to first quickly sear the meat over medium - high heat to get char marks, then move it to the low - temperature area for simmering, to avoid overcooking on the outside while the inside remains raw.