Place the chicken into a sealable bag. Place the peppers and onion into a separate sealable bag. Add the olive oil, lemon juice, chili powder, ground cumin, cayenne pepper, salt, pepper, and garlic to a jar with a screw top or tight fitting lid. Shake until well combined. Pour 1/3 over chicken, 1/3 over vegetables and reserve the remainder in the jar for using when cooking the chicken fajitas. Seal the bags tightly and refrigerate for one hour to overnight.
When ready to cook, heat a large skillet over medium-high heat. Pour vegetable bag into the skillet and cook until just tender crisp, about 5 minutes. Remove the vegetables from the skillet to a plate and add chicken strips to the same skillet. When the chicken is cooked throughout, add vegetables back to the skillet along with the reserved marinade.
Serve with tortilla and optional garnishes.
Notes
To store leftovers. Chicken Fajitas can be stored in the refrigerator for up to 3 to 4 days after they are cooked. This is the food safety limit of time in the fridge for cooked chicken, so if you are not going to eat the cooked fajitas in a couple of days, you should freeze them according to the Freezer directions to follow. Make sure the chicken fajitas are stored in air-tight bags or containers when placed in the fridge.When ready to serve, reheat on the stove at medium heat until warmed throughout. You can also reheat in the microwave on 80% power in 30-45 second increments, depending on the wattage of your microwave.To freeze. These make a delicious freezer meal. Cook and cool completely. Portion into airtight, freezer-safe container(s) or bag(s). Freeze up to 3 months.To serve. Thaw overnight in the refrigerator and reheat in a skillet on the stove at medium heat until warmed throughout. You can also reheat in the microwave on 80% power in 30-45 second increments, depending on the wattage of your microwave.