Cast Iron Steak Fajitas
The key to restaurant-style fajitas is a two-pronged attack: a potent, acidic marinade that tenderizes the steak, and searing, high heat that creates a flavorful char on both the meat and the vegetables. Slicing the cooked steak correctly - thinly, and against the grain - is the final, non-negotiable step that ensures every bite is tender.
Ingredients
For the Steak
- 2 pounds flank steak
- 1/4 cup avocado oil
- 1/3 cup fresh lime juice
- 1 tablespoon ancho chili powder
- 1 1/2 teaspoons ground cumin
- 1 1/4 teaspoons Mexican oregano
- 1 teaspoon smoked paprika
- 1 teaspoon granulated garlic
- 1 teaspoon onion powder
- 2 teaspoons Diamond Crystal kosher salt
For the Vegetables
- 1 large white onion sliced into strips
- 1 red bell pepper sliced into strips
- 1 yellow bell pepper sliced into strips
- 1 green bell pepper sliced into strips
- 1-2 serrano peppers thinly sliced (optional)
For Serving
- 8 to 12 flour tortillas
- Sour cream guacamole, salsa, shredded cheese
Instructions
- Mix the avocado oil, lime juice, and all steak seasonings in a large zip-top bag.
- Add the flank steak to the bag, seal it, and massage the marinade into the meat.
- Refrigerate for at least 1 hour or up to 6 hours for best flavor.
- Remove the steak from the refrigerator 30-45 minutes before cooking.
- Preheat the grill to high heat (450-500F).
- Place the marinated steak on the hot grates and cook for 4-6 minutes per side for medium-rare.
- Transfer the steak to a cutting board and tent with the foil. Rest for 10 minutes.
- While the steak rests, heat a cast-iron skillet on the grill with a splash of oil.
- Add the sliced onions and peppers to the skillet, cooking for 8-10 minutes until charred but still crisp.
- Slice the steak thinly against the grain.
- Serve the steak and vegetables with the warm tortillas and desired toppings.
Notes
Slicing against the grain is essential for tender meat.
Look for the direction of the muscle fibers and cut across them, not parallel.