Combine all of the marinade ingredients in a medium size bowl or shallow dish and mix together well. Set the dish to the side.
Next cut the chicken breasts into thin strips. I like to start by pounding the breasts with a meat pounder to get an even thickness. Then I slice the chicken into roughly ¼-inch strips.
Add the chicken strips to the marinade and toss making sure all the chicken is evenly coated. Cover with foil or a lid and marinate in the refrigerator for 30 minutes or up to 1 hour.
While the chicken is marinating, slice the green bell pepper, red bell pepper, and yellow onion into strips.
Heat a large skillet over medium-high heat and add 1 tablespoon of oil. Add the chicken strips to the skillet along with all the marinade and sauté for roughly 3 minutes on the first side and 2-3 minutes on the second side. Be careful not to overcook the chicken. Once done, remove the chicken from the skillet and set aside on a separate plate. Cover with foil to keep it warm.
Lower the heat to medium and add another tablespoon of oil to the skillet. Add the sliced bell peppers and onions along with 1 tablespoon of water. Use a wooden spoon to scrape up any pan drippings leftover from the chicken. Sauté the veggies for 3-5 minutes until they are tender but still slightly crisp.
Now add the chicken back to the skillet and mix with the veggies. Cook for 1 more minute.
Serve these chicken fajitas with warmed tortillas and your favorite toppings.
Notes
Don’t skip the marinade! The marinade is key to making these fajitas taste amazing.
Use fresh lime juice and fresh garlic in the marinade. It gives it a better flavor and really makes a difference.