1. Marinate the Chicken
- Slice the chicken thighs into 1-inch wide strips.
- In a medium bowl, combine the lime juice, soy sauce, liquid smoke, cumin, salt, chili powder, smoked paprika, onion powder, cayenne pepper, cilantro, and garlic. Stir well.
- Add the chicken to the marinade and toss until fully coated.
- Let the chicken marinate for at least 15 minutes, but ideally up to 24 hours in the refrigerator for maximum flavor.
2. Prepare the Vegetables
- Slice the bell peppers into thin strips.
- Cut the onion in half, then slice into thin half-moon shapes.
- Set the vegetables aside while the chicken marinates.
3. Sear the Chicken
- Heat a 12-inch cast iron skillet (or your sturdiest pan) over medium-high heat for at least 2 minutes.
- Add 2 tablespoons of vegetable oil and swirl to coat the pan.
- Using tongs, place the chicken strips into the pan, shaking off excess marinade. Do not overcrowd the pan—cook in batches if necessary.
- Sear for about 2 minutes per side until the chicken is browned.
- Add 1 tablespoon of butter to the pan, letting it melt under the chicken for extra richness.
- Flip the chicken and cook until the internal temperature reaches 165°F (or cut a piece open to check that it’s fully white inside).
- Transfer cooked chicken to a plate and cover loosely with foil to keep warm.
4. Cook the Peppers and Onions
- In the same pan, add 2 more tablespoons of oil over medium-high heat.
- Toss in the sliced peppers and onions, sprinkle with 1 teaspoon of salt, and pour in any remaining chicken marinade.
- Cook for 2 to 3 minutes, stirring occasionally. Adjust cooking time depending on your preference—traditional fajitas have slightly firm peppers, but you can cook them softer if you prefer.
- Once done, return the chicken to the pan and toss everything together.
5. Warm the Tortillas
- Heat a clean, dry skillet over medium heat.
- Warm the tortillas one by one, adding a sprinkle of cheese while heating if desired.
- Once warm, keep tortillas wrapped in a clean kitchen towel until ready to serve.