How to Cook the Costco Flank Steak in an Air Fryer!

Costco sells USDA Choice Grade Flank Steak and it is a great cut of beef.  There are a lot of different ways of cooking flank steaks but today I want to show you how to cook them in an air fryer.  The flank is one of the better steaks to cook in an air fryer as it is naturally lean and will not create a mess from dripping grease.

The recipe I am sharing is relatively simple but has a few critical points.

Flank steak can be incredibly tough if you don’t treat it right but this recipe will always turn out tender because of three main steps:

1. Marinate in salt to relax the meat fibers.
2. Cook to Medium Rare so it doesn’t turn to leather.
3. Slice super thin AGAINST the grain.

The Flank Steak is One of the Best Steaks at Costco

The quality of steaks at Costco is “hit or miss” and depends entirely on how the Butcher department handles the meat.

Most of the steaks you find in the meat counter have been Blade Tenderized. This means that they have been run through a mechanical device and punched full of holes by needles.

While Blade Tenderization does increase the tenderness of steaks it also introduces the possibility of bacterial contamination.  As a result the steaks are labeled as having to be cooked to an internal temperature of 165F which is way over cooked and ruins a steak.

Some of the steaks that Costco routinely Blade Tenderizes are:

• Tri Tip
• Ribeye
• Flap
• New York Strip

Fortunately Costco does NOT currently use Blade Tenderization of the Flank Steaks so you can safely cook them to Medium Rare.  Just in case your warehouse is run different from mine though, make sure you check the package label.

I also like that the steak is USDA Choice instead of the more expensive Prime.  Some steaks, like Ribeyes, have a lot of marbling so the difference between Choice and Prime is important.  Other steaks, like Flank and Tenderloin, are naturally lean and the quality difference between Choice and Prime is negligible.

Marinate the Steak

My take on steak marinades is different than what you will read from other food bloggers.

A lot of folks create incredibly complex marinades with 15 different ingredients, etc.  The reality is that the only ingredients that actually penetrate INTO the meat are Salt and Water.  Everything else sticks to the surface of the steak.

The salt from a marinade will penetrate into the meat and help the muscle fibers relax which makes the meat more tender.

To this end my marinade is incredibly simple:

• 1/2 cup of Soy Sauce

Although the marinade is simple there is a trick that’s important.  I marinate the steak in soy sauce for two hours at room temperature.

Marinating at room temperature helps the salt penetrate faster than if it was in the refrigerator.  It also helps bring the steak closer to room temperature so it cooks more evenly and faster.

I put the steak in a shallow pan, pour in the soy sauce and cover with aluminum foil.  After one hour flip the steak over and marinate for one more hour.  You can skip the pan and use a one gallon Ziploc bag if you like to live dangerously!

Cook the Steak in Your Air Fryer

When the steak has marinated for two hours take it out of the soy sauce and pat it completely dry with paper towels.

I cooked the steak in my Ninja Foodi Air Fryer so if you have a different model you may need to adjust time and temperature.

The instructions for using the Ninja Foodi are:

• Place dried steak on the mesh tray.
• Set the cooking function to Air Fry.
• Set the Time to 10 minutes.
• Set the Temperature to 425F.
• Turn on the air fryer and wait until it reaches temperature and has cooked the steak for five minutes.
• Open the air fryer, flip the steak and cook for five more minutes.
• Check internal temperature with a digital thermometer and remove when it reaches the doneness you prefer.

After 10 minutes at 425F this steak was perfectly Medium Rare.  If you prefer your steaks at Medium then increase the cooking time to 12 minutes and flip after six minutes.

Remove the steak from the air fryer, place on a tray and cover loosely with foil as it rests for at least 15 minutes.

Slicing the Steak Correctly

The last step to making sure that the flank steak is super tender is slicing.

The flank has a super tight, well defined grain structure that runs along the length of the steak. It is critical that you slice the flank AGAINST the grain to get tender meat.  If you slice WITH the grain then this will be the chewiest steak you have ever eaten.

In addition to slicing the steak against the grain you need to slice it as thin as possible.  I have the best luck slicing thinly using a granton edged meat slicer.

Serving

Once the flank has been properly cooked and sliced then you can add whatever flavor profiles you like.

You can:

• Serve it in tacos
• Make a steak salad
• Toss with pesto and pasta
• Top with chimichurri and serve with mixed veggies and scalloped potatoes.
• Make flank steak sandwiches
• Add to Ramen
• Serve with salsa, guacamole, rice and beans.

I served this batch up on top of the Cauliflower Rice Stir Fry from Tattooed Chef for an ultra lean, low carb, flavor packed meal.

Price of Flank Steak at Costco

The flank steak is Item Number 33977 and is found in the meat counter coolers.

The steak currently costs $8.99 and comes with two steaks per package.  The total weight of the steaks will be around 3 pounds so expect to pay about $30 for a package.