Keto Flank Steak is super simple to make and perfect for family dinners. With fresh rosemary, garlic, and a kick of lemon, this meat is sure to leave your taste buds doing a happy dance. I like to serve it with a drizzle of Keto Chimichurri sauce for an extra pop of flavor.
My first foray into the world of flank steak was at a Brazilian steak house we used to frequent before the world went haywire.
Knowing that it was a tougher cut, I was hesitant to try it. But served with Chimichurri, it was absolutely magical. I was surprised at how much flavor it had!
Even more surprising is that it quickly became one of my teen boys' favorite cuts, even when more expensive options were available.
Since then, it makes a regular appearance on our dinner table. I have tried many marinades, and this one is among the favorites!
This Keto Flank Steak Recipe is one I think you'll turn to again and again.
What is Flank Steak?
Flank steak, which comes from the lower belly, is a great cut when you are cooking for a crowd because it comes in large pieces. It is thin enough that it cooks quickly but thick enough that you can cook it to medium-rare and still get a decent char.
Flank steak is great for grilling, large air fryers, or on a large indoor grill top.
Shopping for Flank Steak
These days, flank steak costs almost as much as a strip steak. Look for a deep red color with some fat running along the length of the muscle. You want a smooth piece that is free from any gouges.
How Do You Cut Flank Steak?
Like skirt steak, it is essential to cut flank in this slices at an angle against the grain.
Can I Skip Marinating the Steak?
You can, and my boys have cooked flank steak with just a dry rub on occasion when they weren't in the mood for what I was making and didn't have another plan.
That said, I highly recommend that you take the time to marinate it if at all possible. Because it is a tougher cut than some, it benefits from a little extra love. Even an hour will make a difference.
Is Soy Sauce Keto-Friendly?
This is a debated issue. Though soy sauce is low in carbs, many agree that it is not good for a keto diet. It contains both gluten and soy, neither of which is considered ok for strict keto.
(That said, if it works for you, go for it.)
A cleaner ingredient is coconut aminos, which is what I've used here. You can find coconut aminos in most grocery stores, or you can order it online.
Can This Recipe Be Made Ahead of Time?
You can marinate the flank steak up to two days ahead of time, but I recommend leaving the lemon zest and juice off if you are planning on doing this. I often do - flank is a chewy cut that benefits from marinating.
Leftovers will keep in a sealed container in the refrigerator for up to three days.
- For a luxurious meal, serve this with Keto Cauliflower Mac and Cheese.
- BBQ Cauliflower Wings are a fun side that both kids and adults will love.
- Looking for something simple but delicious? Try Roasted Cauliflower, Asparagus, or Crispy Brussels Sprouts.
- Keto Creamed Spinach is a delicious low carb twist on a classic that you are going to love!
- Looking for more steak inspiration? This Pan Seared Ribeye is always a hit!
Air Fryer Keto Flank Steak
It is no secret that I love cooking in my air fryer, and this recipe is no exception.
I've got full instructions below, but one thing to remember is to make sure that the meat fits into your air fryer. You can always cut it, but I find this is easier (less messy) to do before the beef has marinated when it is dry.
I don't normally focus on preheating my air fryer because it doesn't make much difference with the model I have. The exception to this is with steak, where preheating helps it develop a nice crust.
Since all air fryers cook a little bit differently, make sure you use an instant-read thermometer to ensure that you achieve your desired doneness.
Keto Flank Steak
- Air Fryer or Grill
- Combine the avocado oil, coconut aminos, Dijon mustards, rosemary, lemon juice and zest, garlic, salt, and pepper in a blender. Process until smooth.
- Place the steak in a zip-top bag and pour the marinade over.
- Marinate for at least 1 hour and up to 4 hours. (If you want to marinate overnight, omit the lemon.)
- Preheat the grill to medium-high. Add the flank steaks and grill for about 3 to 5 minutes per side, until an instant-read thermometer inserted in the thickest part registers 120° F for medium-rare and 130° F for medium.
- Transfer to a cutting board. Allow to rest for 5 minutes and then slice against the grain.
- Preheat the air fryer to 400.° F. Place the flank steak in the air fryer in a single layer. Cook for 8 to 10 minutes, flipping halfway through, until an instant-read thermometer inserted in the thickest part registers 120° F for medium-rare and 130° F for medium.