Flank steak is a cut of beef with a lot of potential.
Known for having a big flavor that can hold up to different preparation methods, flank steak can be an excellent addition to your summer barbecues, family meals, or romantic dinners.
But, as with all cuts of steak, it needs to be cooked right. Cooked wrong, you end up with a tough and unappealing steak.
Flank steak is a little different from the popular steak cuts. From the abdominal muscle, flank steak has more fibers and less fat.
And it’s also typically a big chunk of meat, weighing in at over two pounds. By learning the perfect temperature of flank steak, you can understand how to cook all that weight, without overdoing it.
In this guide, we’ll cover how you can use temperature to nail the cooking of your flank steak, plus some different methods of preparation.
When you understand flank steak, you can really take your backyard grill up a notch!
The Internal Temperature Of A Perfectly Done Flank Steak
Temperature is a key consideration when it comes to cooking any form of steak.
The internal temperature will determine just how “done” your flank steak is, and can be what separates your perfectly pink cut from a dry and overdone steak.
But with that said, there’s no perfect temperature for steak. For those who love a rare steak, the ideal temperature will be on the low side.
And if you prefer your flank steak medium to well done, you’ll want to wait for the inside to get a little hotter.
So, the ideal temperature for flank steak could be anywhere between 120 degrees Fahrenheit and 140 degrees Fahrenheit. And this is the final temperature.
You want to take it off the heat a few degrees before it reaches this.
Finding The Perfect Flank Steak Temperature
The perfect flank steak temperature is going to depend on your own preferred method of enjoying steak.
If you like your flank steak rare, then look for an internal temperature between 120 and 125 degrees Fahrenheit.
For a medium to medium rare flank steak, the ideal temperature range is between 130 and 140 degrees Fahrenheit.
To achieve this perfect temperature, use a meat thermometer to probe along the steak.
When the flank steak internal temperature is between 5 and 10 degrees below your preferred endpoint, remove the meat from the heat.
External heat will continue to cook the interior even as the steak rests, raising the temperature by a few degrees.
If you prefer your flat iron or sirloin to be as rare as possible, you might naturally cook for the lower end of the temperature scale when working with flank steak.
However, flank steak is a very different cut of meat to these choices, and it has to be treated carefully.
Flank steak comes from the abdominal, so this is meat that had to do some work. Because of this, it has less fat, and more fiber.
You can enjoy a flank steak rare, but it’s unlikely to have the melt in the mouth texture of a fatty steak. Instead, you might find the flank steak is a little chewy, and perhaps even rubbery.
A good marinade can help achieve a softer texture in a rare flank steak, but a few extra minutes on the grill will work better.
The heat will have time to break down the collagen, providing that perfect tenderness. You might lose some moisture in the longer cooking process, but it’s worth it for the tender finish.
For that reason, we believe the perfect internal temperature for flank steak is 135 degrees Fahrenheit. At this point, the heat has been able to tenderize the meat, but most of the moisture is still locked in place.
To achieve this 135 degree internal temperature, take the steak off the heat when it reaches around 128 degrees Fahrenheit. As the steak rests, the temperature will increase.
Now you know what temperature to look out for, let’s cover some other tips for achieving the perfect flank steak.
Marinade Or Rub?
Both marinades and rubs work well with a flank steak, as the beefy flavor holds up to some complex additions. Our preferred choice is the marinade.
This gives the flank steak a rich dose of flavor, and might even help achieve that tender texture we all crave.
There’s a long-standing belief that using a marinade can help you achieve a softer texture. This is partly true. A marinade can help to tenderize meat, lock in moisture, and add some extra flavor.
However, they aren’t the miracle tenderizer so many assume they are. A good marinade will only be able to penetrate a few millimeters below the surface.
So, it might not transform your flank steak, but we still think it’s worth doing.
You also have to be careful not to over marinate your meat. Left too long in acidic marinade, the exterior of the steak will start to toughen. We think two hours is perfect.
Achieving the perfect marinade that tenderizes without toughening is all about perfecting the ratio of acids to other ingredients.
Some acidic fruits such as pineapple and papaya can tenderize while adding flavor. Other options include vinegar, which adds sharpness while breaking down fibers.
Alternatively, you could use a rub. Rubs are fantastic if you don’t have much time, but want to add some extra oomph to your steak.
A rub won’t tenderize at all, so you probably want to use a meat tenderizer first. To do this, place your steak in a food storage bag, remove the air, and seal.
Lay the bag flat on the counter. Pound the meat with your steak tenderizer, being sure to work evenly across the cut. Remove the steak from the bag, massage in your rub, and you’re ready to start cooking.
Our Favorite Marinade For Flank Steak
This is our favorite marinade for flank steak. Flank steak is a popular choice for fajitas, and we like the punch of Mexican flavoring that this marinade gives.
Flank Steak Marinade Recipe
- ⅓ cup of soy sauce (substitute tamari sauce or coconut aminos if avoiding soy sauce)
- ¼ cup of freshly squeezed lime juice
- 4 green onions, washed and sliced into halves
- 2 large cloves of garlic
- ½ tsp red pepper flakes
- ½ tsp ground cumin
- 3 tbsp Mexican brown sugar (substitute standard brown sugar if you can’t find Mexican)
Add soy sauce, lime juice, green onion, garlic, red pepper flakes, cumin, and sugar to a blender. Blend to a thick paste, and then slowly mix through the olive oil.
If you don’t have a blender, mince the garlic and finely slice the green onions, and mix by hand.
Place the flank steak into a food storage bag with a zip top. Remove the air from the bag, and then seal it. Leave the steak to marinade for two hours or longer in the refrigerator.
Do not leave for longer than 24 hours.
Cutting Flank Steak
Another way to ensure your flank steak is as tender as it can be is to cut it correctly. Flank steak should be cut against the grain, to break through the connective tissue.
By breaking these bonds, the steak can tenderize during a quicker cooking process.
Before you begin slicing, make sure you have a sharp knife. The first and last slices can be difficult, but a sharp knife can help overcome this problem.
Next, look for the direction of the grain. This is the way the muscle fibers run along the meat. You want to slice across them, rather than parallel. Hold the knife at a 45-degree angle, and make a smooth cut.
Cooking Flank Steak On The Stove Top
Cooking flank steak on the stove top can provide you with a good sear and a nice crust. This is a great method if you like cooking steak to be quick and easy.
If you’re planning a speedy dinner, combine the stove top method with a dry rub. Fajita seasoning works wonders for a flavorful flank steak dinner, but you can also get away with using just salt and pepper.
Start with a heavy pan, such as a cast iron. This can give you a good crust and an even cook. You want to cook the steak on a high heat over a short period of time, and the heavy cast iron is ideal for this.
And because cast iron pans hold onto heat, you only need to use a medium-high flame. This is easier to control.
Spray the pan with olive oil, and place on a medium high heat. Let the pan heat properly before you add your steak. Place the flank steak in the pan, and allow it to cook for roughly four minutes.
Don’t move it, prod it, or poke at it, no matter how tempting it might be.
When four minutes are up, flip the steak, and cook the other side.
Remove the pan from the heat, and grab your meat thermometer. Flank steak tends to have an uneven thickness, so you want to check the temperature in a few different places.
The temperature should be around 125 to 130 degrees Fahrenheit, for that perfect 135 degree finish. If you aren’t there yet, put the pan back on the heat for a short period (you probably won’t need very long).
If you are happy with the temperature, remove the steak from the pan, place it on a plate, and leave it to rest for around ten minutes. Then you can slice and enjoy.
Grilling Flank Steak
Flank steak is an exceptional choice for a barbecue. The best way to grill flank is with a quick sear over a medium high heat. Your steak should then be ready to go, or you can finish the cooking process in a cool zone on the grill.
We think grilled flank steak goes best with a marinade, to prevent the risk of a rubbery texture. Before you start grilling, wipe away the excess moisture from the marinade.
This way, you can achieve a good crust. If you aren’t using a marinade, pat away any moisture, and apply your dry rub.
For a charcoal grill, you want to build a hot and cool zone using coals. Place the flank steak on the hot area to begin with. Cook for roughly four minutes, and flip. Cook the other side for around four minutes as well.
Move the steak to the cool zone, and check the temperature. If it’s between 125 and 130 degrees, remove the steak to rest.
Otherwise, allow it to keep cooking in the cool zone until you’re happy with the temperature. Then, leave it to rest, slice, and serve.
Flank steak is a little different to other popular cuts, thanks to the higher fiber content, and lower amount of fat. But with some careful cooking and preparation, you can have a perfectly tender and flavorful meal.