Preheat your skillet to medium heat and add your oil, or the option you prefer for your pan. Combine all your spices in a bowl and mix well
Season the chicken, saving about a fourth of it for the vegetables
Cook your chicken for about 5-7 minutes on each side, or until the internal temp reaches 165 degrees
While your chicken cooks, cut your onion and all of your peppers into slivers
Once your chicken is cooked, add in your vegetables and sprinkle them with the remaining seasoning
Saute the veggies until they caramelize (about 10 minutes), stirring or tossing occasionally
While the vegetables cook, slice the chicken into thin strips
As the vegetables are finishing, add your chicken into the skillet and mix thoroughly. Remove from heat
Heat up some tortillas in the microwave or on the stovetop and fill with your fajita mixture. Enjoy!