I combined the marinade with the sliced, raw chicken in one bag and froze it. In another bag I combined the pepper and onion slices and froze them separately. I thawed the chicken, cooked it and then cooked the peppers and onions from their frozen state. The fajitas tasted pretty good, but the vegetables were a little mushy. If I were to try to it again I might consider using a frozen veggie mix from the grocery store as the flash frozen vegetables may not be as mushy. Or I would just go with fresh vegetables like I did for this newer rendition.
I realized with my frozen, pre-cooked chicken I can make fajitas or tacos fairly easily and this replaced having dedicated fajita meat in the freezer. It is fairly easy although it does require prepping the peppers and onions on the day of. You may be able to save some time with pre-cut peppers and onions from the produce section or salad bar at your grocery store.