Quick Answer
London broil is a flank steak that can be cut into thin strips to use for stir-fry. The key is to slice the steak across the grain, at a 45 degree angle. This will ensure the meat is tender when cooked quickly in the stir-fry. Cut the steak into 2-3 inch sections first, then slice very thin strips across the grain about 1/4 inch thick.
Cutting Against the Grain
When cutting any steak for stir-fry, it’s important to slice against the grain of the meat instead of with the grain. The grain of the meat refers to the direction of the muscle fibers that run through it. Cutting against the grain shortens these fibers so they don’t become tough and chewy when cooked.
Slicing steak with the grain keeps the fibers long and they can contract and become tougher when exposed to heat. Cutting across the grain keeps the fibers short for tenderness.
Slicing on an Angle
Cutting the London broil on an angle or bias allows for slightly longer cuts of meat. This helps the thin slices hold together better during cooking.
To slice on a bias, position the knife at about a 45 degree angle to the cutting board and make your slices. Rotate the steak 90 degrees after each cut to maintain the angled slices.
Slicing Consistent Thin Strips
London broil can be quite thick, so it’s important to slice it very thin for stir fries. Each slice should be about 1/4 inch thick.
An easy way to achieve this is to first cut the London broil into 2-3 inch sections across the grain. This makes the steak easier to handle for thin slicing.
Place one section at a time flat on the cutting board and slice across the grain into very thin strips, keeping them as consistent in thickness as possible. Thin and uniform pieces will cook quickly and evenly in the stir-fry.
Cutting Beef Against the Grain
Cutting beef against the grain is a simple technique that makes a big difference in tenderness. Here’s a guide on how to do it properly:
Find the Grain
– Look closely at the meat fiber direction. You’ll see the muscle fibers running in long lines through the meat. This is the “grain” of the beef.
Cut Perpendicular to Grain
– Place your knife at a 90 degree angle to the grain lines and make your cuts. This severs the long muscle fibers into shorter pieces.
Rotate as You Go
– As you slice, rotate the beef 90 degrees between cuts to maintain cutting against the grain. This ensures all fibers get cut for tenderness.
Cut Across Whole Cuts
– For roasts or larger steaks, first slice across the grain into smaller sections. This makes the meat easier to manage for thin slicing.
| Do This | Not This |
|---|---|
| Cut across the grain lines at a 90 degree angle. | Cut parallel to the grain lines. |
| Rotate meat and repeat slicing at a 90 degree angle. | Keep slicing in the same direction as the grain. |
Following these simple steps of cutting against the grain will reward you with much more tender beef for stir fries, fajitas, roasts and steaks.
Tips for Stir-Frying London Broil
London broil can become tough and chewy if not cooked correctly. Here are some tips for stir-frying London broil for tender results:
Cut Across the Grain
This shorts the muscle fibers so they don’t contract and toughen. Cut very thin strips for quick cooking.
Marinate the Meat
A marinade with acid tenderizes the beef and adds flavor. Marinate for 30 minutes up to overnight.
Get the Wok Very Hot
Use high heat and keep ingredients moving for a good sear while cooking quickly.
Don’t Overcook
Cooking for just 2-3 minutes seals in juices and prevents toughening. Slice beef thin so it cooks fast.
Velvet the Meat
A velveting marinade uses cornstarch and egg whites to coat the meat and keep it tender. Velvet for up to 2 hours before cooking.
Slice Across the Grain to Serve
This finishes separating the muscle fibers so the cooked meat will be bite-tender.
Conclusion
Cutting London broil into thin strips for stir-fry is easy when you follow a few simple steps. Be sure to slice against the grain of the meat on an angle. Cut the steak into manageable sections first, then slice very thin strips about 1/4 inch thick across the grain. This severs the muscle fibers so the meat cooks up tender in the quick, high-heat stir-fry cooking process. Use marinades and velveting techniques to further ensure the beef comes out juicy and tender.