Easy Air Fryer Steak Fajitas are ready in 20 minutes or less. Use the extra time to make sides and turn this low-carb dinner into a Tex-Mex feast the whole family will enjoy.
Cooking steak in an air fryer gives you a nice char on the outside while keeping the interior juicy. Cutting the steak into cubes or strips before cooking speeds the process and increases surface area for caramelization, which maximizes flavor.
This method is inspired by popular air-fried steak bites and adapts perfectly to fajitas. A simple fajita rub, bell peppers, and onions deliver bold Mexican-inspired flavors, and the recipe is easy to customize for low-carb or gluten-free diets.
Why you’ll love this recipe:
- Ready quickly—no marinating required; the spice rub locks in flavor.
- Easy to swap in different vegetables to suit your tastes.
- Keto-friendly and gluten-free options are simple depending on how you serve it.
Note: This recipe works well in a variety of air fryers. We test in a 5.8-quart Cosori and a 4-quart Ninja. Cooking time and basket capacity will vary by model, so use the guidance and check doneness with a thermometer. Always follow your appliance manufacturer’s instructions.
Ingredients
Here’s what you’ll need:
- Steak – Top sirloin filets or top sirloin cut into 1½–2 inch cubes. These sizes cook evenly and make it easy to check internal temperature. Flank or skirt steak can also be used—adjust cooking time for thickness. Cut all pieces to similar size so they cook uniformly.
- Onion and bell peppers – sliced into strips or diced. Smaller pieces may fall through some baskets unless lined or contained.
- Fajita seasoning – store-bought or use the DIY low-carb blend below.
- Lime – for squeezing over the finished fajitas.
Customize the Vegetables
Mushrooms, cauliflower, broccoli, and grape tomatoes all work well. Chop firmly so they cook quickly, or be prepared to remove the meat and finish the vegetables a little longer. If you add extra vegetables, the basket will be fuller—shake more frequently and allow a few extra minutes of cook time.
Low-Carb Fajita Seasoning
Make your own seasoning so you can adjust heat and sweetness. Omit the sweetener or use a sugar substitute to keep it keto. This mix yields about 1½ tablespoons.
- 1 teaspoon chili powder
- ½ teaspoon paprika
- ¼ teaspoon cumin
- ¼ teaspoon garlic powder
- ¼ teaspoon onion powder
- ½ teaspoon oregano
- ½ teaspoon salt
- ⅛ teaspoon cayenne pepper (optional)
- ½ teaspoon sugar substitute (optional)
Directions
Simple, straightforward steps:
Preheat the air fryer to 390 °F so it’s hot when you add the meat and vegetables. You can line the basket with parchment or foil if desired.
- Pat the meat dry, cut into cubes, and toss with olive oil and fajita seasoning.
- Slice the vegetables. Add the beef and vegetables to the air fryer and gently shake to combine. Some oil and seasoning should coat the peppers and onions; if not, mist with a little more oil.
- Cook at 390 °F for about 9 minutes total, shaking halfway through. Exact time depends on your air fryer and basket fullness.
- Check doneness by lifting a piece and using an instant-read thermometer. The USDA recommends 145 °F for beef; remove at 130–135 °F for a warm, pink center, as temperature will rise slightly while resting.
- Let the steak rest a few minutes, then slice against the grain into bite-sized strips. Squeeze lime over the top and serve.
Low-Carb Serving Ideas
Serve these fajitas with a variety of bases and toppings to suit your diet:
Bases:
- Low-carb flour tortillas
- Lettuce wraps (romaine or butter lettuce)
- Salad base
- Cauliflower rice (raw or cooked)
- No base—serve as a plate with toppings
Toppings:
- Sour cream or Greek yogurt
- Salsa
- Shredded cheese
- Tomatoes, avocado, or guacamole
- Cilantro and jalapeños
Storage and Reheating
- Store: Keep leftovers in an airtight container in the refrigerator for up to 3 days.
- Reheat: Warm in a skillet over medium-high heat or use the microwave until heated through.
- Freeze: Freeze in an airtight container for up to 3 months.
More Easy Tex-Mex Recipes
Healthy Taco Salad Dressing with 2 Ingredients!-
One Avocado Guacamole Recipe
-
Mexican Street Style Cauliflower (Low-carb Elote)
Want more easy, healthy, carb-conscious recipes?
📋 Recipe
Air Fryer Steak Fajitas
Equipment
- Air Fryer
Ingredients
- 1 pound top sirloin filets or top sirloin cut into 1½–2 inch cubes
- 1 Tablespoon olive oil
- 1 Tablespoon fajita seasoning
- ½ cup sliced bell pepper
- ½ cup sliced onion
- 1 lime, for serving
Low-Carb Fajita Seasoning
- 1 teaspoon chili powder
- ½ teaspoon paprika
- ¼ teaspoon cumin
- ¼ teaspoon garlic powder
- ¼ teaspoon onion powder
- ½ teaspoon oregano
- ½ teaspoon salt
- ⅛ teaspoon cayenne pepper (optional)
- ½ teaspoon sugar substitute (optional)
Instructions
- Preheat empty air fryer with crisper plate or basket in place to 390 °F for 3 minutes.
- Pat meat dry. While the air fryer heats, toss beef cubes with olive oil and fajita seasoning.
- Place seasoned beef, sliced bell peppers, and onions into the preheated air fryer and gently shake to combine. If the vegetables don’t get coated, spritz a little more oil.
- Cook at 390 °F for about 9 minutes total. Pause and shake after 3 minutes, then continue shaking at 2-minute intervals until the beef reaches desired doneness. Use an instant-read thermometer: USDA recommends 145 °F; remove at 130–135 °F for medium-rare to medium.
- Allow steak to rest for a couple of minutes, then slice against the grain into bite-sized pieces. Squeeze lime juice over the top and serve on tortillas, lettuce wraps, cauliflower rice, or salad with desired toppings.
Low-Carb Fajita Seasoning
- Mix the spices together in a small bowl. Yield is about 1½ tablespoons.
Notes
See the tips, topping ideas, and step-by-step photos above for more help.
Stovetop Option: Heat 1 Tablespoon olive oil in a hot skillet (preferably cast iron). Sear beef cubes until browned on each side and cooked to your preference. Let rest and slice. Sauté vegetables 5–7 minutes until softened and charred.
Air Fryer Disclaimer: Results may vary by brand and size of air fryer. Always follow your appliance’s instructions and adjust cook times as needed.
Storage: Refrigerate leftovers in an airtight container up to 3 days. Reheat in a skillet or microwave. Freeze up to 3 months.