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Flat-Iron Tacos

Flat-Iron Tacos

These steak tacos are so delicious they will wow you! Aji is a South American sauce prevalent in Columbia and Peru. Depending on the region, this sauce (or sometimes a chunky salsa) can range from mild to super hot. We'll be using the milder version to marinate the flat-iron steaks for this recipe.
Photo by: bhofack2/depositphotos
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Course: Main Dish
Cuisine: Latin American
Prep Time: 25 minutes
Cook Time: 10 minutes
Total Time: 35 minutes
Servings: 4 People
Calories: 767kcal


  • 2 pounds flat iron steak
  • 12-14 corn tortillas
  • 1 1/2 cups guacamole (lettuce, pico de gallo, queso, or cotija cheese)
  • for marinade:
  • 1 onion small, roughly chopped
  • lime juice aim for two medium limes
  • 2 jalapenos seeded and roughly chopped
  • 1/4 cup cilantro
  • 2 cloves garlic minced
  • 1 tablespoon olive oil
  • 2 teaspoons salt
  • 1-2 teaspoons habanero pepper sauce (optional)
  • 1 teaspoon black pepper


  • Place all marinade ingredients into a food processor. Process until mixture is thick and smooth. Add more lime juice or oil if mixture remains chunky.
  • Place flat iron steaks in a resealable plastic bag. Pour aji marinade over steaks and work it in making sure all surfaces of the meat are well coated. Seal bag and place into refrigerator for 6-24 hours.
  • Preheat grill for medium-high heat.
  • Remove steaks from bag and place onto grill. Cook 5-7 minutes per side or until steak reaches desired doneness. Place tortillas in a large piece of aluminum foil, wrap and place on the cooler part of the grill for about 5-7 minutes, turning once.
  • Once cooked, remove steaks from grill and place onto a cutting board. Remove tortillas and set aside. Slice steaks into thin strips and serve in warmed tortillas with guacamole. If preferred, make a double batch of the aji sauce and reserve half to serve with the tacos.


Things to think about with this recipe:
If you cannot find beef flat-iron steak at your local grocery store, flank steak will suffice. Keep in mind that flank steak is a tad tougher than flat-iron, and might require a longer marinating time.
If you love spicy food, add an extra jalapeno, or a bit more habanero pepper sauce to the Aji mixture. Experiment with the flavors, and create something spectacular that fits your taste buds.


Calories: 767kcal | Carbohydrates: 47g | Protein: 50g | Fat: 43g | Saturated Fat: 12g | Trans Fat: 1g | Cholesterol: 150mg | Sodium: 1374mg | Potassium: 1376mg | Fiber: 12g | Sugar: 3g | Vitamin A: 285IU | Vitamin C: 20mg | Calcium: 102mg | Iron: 7mg