Grilled Steak Fajitas with Corn Tortillas and Guacamole

Juicy marinated flank steak meets smoky charred peppers and onions in soft corn tortillas, topped with creamy homemade guacamole. The steak soaks up lime, cumin, and garlic in a quick marinade, then sears fast over high heat for tender, flavorful strips. Everything comes together in warm tortillas with a squeeze of fresh lime, building a bright, bold dinner you can load up however you like.

By TasteBuds

Recipe details

Yield
4 people
Prep time
25 minutes
Cook time
15 minutes
Total time
45 minutes

Ingredients

  • 1½ lb flank steak
  • ¼ cup fresh lime juice (from about 2 limes)
  • 3 tbsp olive oil, divided
  • 4 cloves garlic, minced
  • 1½ tsp ground cumin
  • 1 tsp smoked paprika
  • 1 tsp chili powder
  • 1 tsp kosher salt
  • ½ tsp black pepper, freshly ground
  • 2 large red bell pepper, sliced into strips
  • 1 large yellow bell pepper, sliced into strips
  • 1 large yellow onion, sliced into thick strips
  • 12 small corn tortillas (6-inch, verify allergen-free labels)
  • 3 medium ripe avocados
  • ¼ cup red onion, finely diced
  • 3 tbsp fresh cilantro, chopped
  • 1 small jalapeño, seeded and minced (optional, for heat)
  • 2 limes, cut into wedges (for serving)

Instructions

  1. Mince 4 cloves garlic.
  2. In a large mixing bowl, whisk together ¼ cup fresh lime juice, 2 tbsp olive oil, 4 cloves garlic, minced, 1½ tsp ground cumin, 1 tsp smoked paprika, 1 tsp chili powder, 1 tsp kosher salt, and ½ tsp black pepper.
  3. Place 1½ lb flank steak in a gallon-size resealable bag or shallow dish, pour the marinade over it, and turn to coat. Seal and refrigerate for at least 30 minutes, or up to 4 hours.
  4. While the steak marinates, slice 2 large red bell peppers and 1 large yellow bell pepper into strips.
  5. Slice 1 large yellow onion into thick strips.
  6. Halve 3 medium ripe avocados, remove the pits, and scoop the flesh into a medium bowl.
  7. Finely dice ¼ cup red onion.
  8. Chop 3 tbsp fresh cilantro.
  9. If using, seed and mince 1 small jalapeño.
  10. Mash the avocado flesh with a fork until mostly smooth but still chunky. Stir in ¼ cup red onion, finely diced, 3 tbsp cilantro, chopped, 1 small jalapeño, seeded and minced (if using), the juice of 1 lime (from the wedges), and a pinch of kosher salt. Taste and adjust salt. Cover and refrigerate.
  11. Heat a grill or grill pan over high heat until very hot.
  12. Remove 1½ lb flank steak from the marinade, letting excess drip off. Grill for 4 to 5 minutes per side for medium-rare, or until the internal temperature reaches 130°F (54°C). The steak will have visible char marks and feel firm but still give slightly when pressed.
  13. Transfer the steak to a cutting board, tent loosely with aluminum foil, and let rest for 10 minutes.
  14. While the steak rests, heat 1 tbsp olive oil in a large skillet over medium-high heat. Add 2 large red bell peppers, sliced, 1 large yellow bell pepper, sliced, and 1 large yellow onion, sliced. Cook, stirring occasionally, until the vegetables are charred at the edges and softened, about 8 to 10 minutes. Season with a pinch of kosher salt.
  15. Warm 12 small corn tortillas in a dry skillet over medium heat for about 30 seconds per side, or wrap in damp paper towels and microwave for 30 seconds, until soft and pliable.
  16. Slice the rested 1½ lb flank steak thinly against the grain.
  17. Cut 2 limes into wedges.
  18. Serve the sliced steak, charred peppers and onions, warm corn tortillas, guacamole, and lime wedges on a platter or in separate bowls. Let everyone build their own fajitas, topping with guacamole and a squeeze of lime.