Best Steak Fajitas Recipe

Making steak fajitas at home is SO easy with this recipe featuring the BEST marinade. Flank steak is coated with taco seasoning, lime juice, and a few secret ingredients, then cooked in a cast iron pan until lightly charred. Serve these sizzling beef fajitas with sautéed bell peppers and onions, tortillas or cauliflower rice, and a bit of guacamole, salsa, and cilantro!

Mexican food always has a special place in my heart. This is probably due to the fact I’ve lived in San Antonino for four years and in Texas my entire life.

And every time I try out a new restaurant, there is one item I HAVE to order.

The steak fajitas.

You can very quickly determine the authenticity of a restaurant based on this dish. If the beef is no good, chances are the rest of the menu will be subpar as well.

When we moved from San Antonio to Austin, it was difficult to find a restaurant that made them as good.

The solution? Learn how to make steak fajitas at home!

After quite a bit of tweaking and recipe testing, I was able to crack the fajita code. Plus, the steak fajita marinade also doubles to make chicken fajitas, too!

With one simple fajita marinade recipe you can have the best of both worlds.

The key ingredient?… Soy sauce!

It gives the flank steak a lovely umami flavor and the perfect amount of saltiness.

Ingredients

The simple ingredients you need to make these steak fajitas include:

• Beef. A huge determinant of how tender or tough the fajitas will come out. You can use any cut of meat including flank, skirt, and flat iron. Make sure you get a cut that is no thicker than 1-inch for the best results. See below for more information.
• Vegetables. The classic bell pepper and onion combo is my go-to. Feel free to add in some mushrooms, zucchini, or squash, too!
• Taco Seasoning Mix. Homemade taco seasoning is the best and is what was used in this recipe, but store bought will also work if you’re pressed for time.
• Honey. Pure maple syrup, agave nectar, or even a reduced amount of liquid stevia extract can be used as well.
• Soy Sauce. This gives the perfect saltiness and umami flavor. Gluten-free soy sauce, or Tamari sauce, have both been tested in this recipe. Substitute for reduced sodium if needed.
• Worcestershire sauce. Seemingly insignificant, but this gives a TON of flavor! Make sure you look for a gluten-free variety if you are Celiac as some may have hidden wheat.
• Lime Juice. Definitely the best citrus to use, but lemon or orange juice can also be substituted.

Best Steak for Fajitas

There are a few different types of steak that are best to use when making beef fajitas:

• Flank Steak – This cut of meat is very lean, which means it is also on the tougher side. It comes from the lower chest and abdominal muscles of the cow. Make sure to slice flank steaks against the grain.
• Flat Iron Steak– Located in the shoulder of the cow, this is a very tender portion of the cow. It’s incredibly flavorful, due to the higher amounts of fat marbling throughout.
• Skirt Steak – The toughest of the three, this cut is from the diaphragm muscle and has a fibrous texture. However, this lean cut of meat has incredible flavor. Marinate it well and slice thin for best results.

How to Make

The basic steps for making steak fajitas are simple to follow. Please see the recipe card for exact ingredient amounts.

Fajita Marinade

Whisk together the marinade ingredients in a large bowl. Add steak and let it sit for 1 hour or up to overnight in the refrigerator. The longer it marinates, the more flavorful and tender the beef will be.

Cook the Vegetables

Sauté sliced bell peppers and onions in oil in a cast-iron skillet over medium-high heat until slightly charred. You want them to be tender, yet still crisp. Remove from the skillet and set aside until ready to serve.

Sear the Steak

Cook steak over medium to medium-high heat for 4-5 minutes per side, or until cooked to your desired doneness. Let any excess marinade drip off the steak before adding it to the skillet. Check with a meat thermometer for doneness. A temperature of 130°-135° is medium-rare, 140° is medium.

Slice the Steak

Let steak rest on a cutting board for 5 minutes before slicing. This resting time will help keep all of the delicious juices in.

Cut steak into thin ¼-½” slices against the grain.

Serving

Serve on a corn tortilla with additional cilantro, sour cream, tomato salsa, or guacamole, or make a rice bowl!

Dietary Modifications

The recipe you’ll find below is already dairy-free as written. Here are some adjustments and substitutions you can make to help it fit your other dietary requirements:

• Gluten-Free – Make sure to use gluten-free soy sauce and Worcestershire sauce.
• Low-Carb – Leave out the honey, or substitute it for monk fruit or liquid stevia.
• Whole30 – Simply swap out the soy sauce for coconut liquid aminos. Also, leave out the honey or replace it with liquid stevia extract.

Meal Prep and Storage

• To Prep-Ahead: Wash and cut the veggies, and make the marinade up to 3 days in advance. You can also marinate the steak for up to 24 hours.
• To Store: Keep leftovers in an airtight container in the refrigerator for up to 3-4 days.
• To Freeze: Seal in a freezer-safe airtight container and freeze for up to 3-6 months.
• To Reheat: Add the steak back to a skillet with a touch of oil. Warm up over medium heat for 5-10 minutes or until heated through.

FAQs

Expert Tips and Tricks

• Cut against the grain. This results in a more tender texture.
• Make it at home. Homemade taco seasoning is not only healthier, but you can also control the spice level.
• Marinate for the minimum. Let the steak sit in the marinade for at least an hour for the best flavor.
• Cast-iron works best. The even and high heat gives the perfect char, and that restaurant sizzle!
• Let it rest. Allow the cooked steak to sit before slicing to retain the juiciness.

Make it a Meal

There are so many incredible side dishes or dips you can serve with these flank steak fajitas to complete the meal. Here are a few of the best Mexican side dishes:

• Mexican Street Corn Salad
• Easy Guacamole Recipe
• Homemade Salsa Recipe
• Mexican Rice
• Avocado Corn Salad
• Tomatillo Salsa Verde
• Cilantro Lime Rice
• Chipotle Fajita Veggies