Prepare Chicken: Season chicken lightly with salt and pepper - pressing the salt and pepper into the meat. Place chicken in a large reusable silicone bag or glass baking dish and set aside.
Marinate Chicken: Add chili powder, kosher salt, paprika, onion powder, garlic powder, cayenne, oregano, pepper, lime juice, olive oil, and fresh cilantro (if using) to a small mixing bowl. Whisk until well combined. Pour the marinade over the chicken, ensuring it is fully coated. Seal and place in the refrigerator for 30 minutes or more.
Cook Chicken: Bring a large cast iron skillet to medium-high heat. Add a oil, swirl to coat the pan. Remove chicken from marinade letting excess marinade drip off; discard leftover marinade. Place chicken in the pan and sear 8-10 minutes or until the internal temperature of the thickest part of the chicken reaches 160 degrees F. (use an internal meat thermometer for accuracy) - during the cooking process turn down the heat, as-needed, if your skillet really gets hot and/or add a little extra oil if the pan is dry - to avoid burning. Squeeze fresh lime juice over chicken and stir. Remove from skillet and let the chicken rest on a plate while you cook the veggies.
Cook Veggies: Keeping pan at medium high heat, add 2-3 tablespoons of chicken broth to deglaze the pan - use a spatula to scrape up the bits from the bottom of the pan. Add garlic and move around pan until it becomes fragrant, approx. 1 minute. Add onion, bell peppers, and the fajita seasoning. Stir to combine. Add additional broth or olive oil to pan if you feel it is getting a bit dry.
Finish Veggies: Sauté for approx. 10-15 minutes or until the peppers have reached your desired doneness (cook shorter for a more firm, but tender pepper - longer for a softer pepper). Taste and add any additional salt or pepper, to taste.
Add Chicken: Return the chicken back to the skillet, along with any juices that have gathered. Stir to combine. Taste and add any additional fresh lime juice, fresh cilantro or salt - as needed.
Serve: Serve on warm tortillas with the fajita veggies, cilantro lime sauce, corn salsa and any other toppings you desire!
Notes
Chicken Options: if you don't want to use chicken breast - chicken thighs could also be used.
Storage: place in an airtight container in the fridge for 3-4 days. We recommend storing the meat, veggies, sauce, salsa, etc., each in a separate container to make reheating easier the next day and to prevent sogginess.
Next Level: we HAVE to give a shout out to this Cilantro Lime Sauce - it is just what you need to take a classic Chicken Fajita Recipe and bring it to the next level. We use it on our Steak Fajitas and everyone LOVES it!