In a bowl mix together lime juice, olive oil, red pepper flakes, cumin, garlic powder, oregano and cilantro. Pour half in to each of two gallon sized freezer bags. Put chicken in one bag, mixing around until chicken is coated with marinade. Remove as much air as possible from each bag, seal and label. Bundle both bags together (use a third bag or rubber bands). Freeze if making ahead, or place in refrigerator until ready to load camping cooler.
To serve: Bring onion and bell peppers along with chicken to camp. The morning of the day you will serve chicken, peel and slice onion into 1/2" rounds. Remove core and seeds from peppers, slicing in half or into quarters. Place onions and peppers into the bag with only marinade. Mix around until coated. Allow to marinade in cooler until dinner time.
Cook chicken over a fire on grate, moving it around to prevent burning until almost cooked through. Add onions and peppers to grate to cook until crisp-tender. Discard marinade. When chicken and vegetables are cooked through, slice thinly and serve on toasted gluten free tortillas, salad, or baked sweet potatoes. Enjoy!