In a small bowl, whisk ¼ cup of the olive oil, orange juice, lemon juice, garlic, parsley, salt, and pepper.

Put the chicken in a gallon-sized resealable plastic bag and pour the marinade over it. Squeeze as much air from the bag as possible, seal the bag, and turn the bag in your hands a few times to ensure all of the chicken pieces are coated in the marinade. Refrigerate for at least 1 hour and up to 24.

Put the bell peppers and onion in a large bowl. Add the remaining 2 tablespoons of olive oil and toss well to coat all of the vegetables. Sprinkle them liberally with salt and pepper.

Prepare your gas grill on high heat. Remove the chicken from the marinade; discard the bag and marinade. Assemble the kabobs by threading a piece of chicken onto a skewer followed by a piece of bell pepper, a piece of onion, another piece of chicken, a pepper, and another onion. Repeat with all remaining ingredients. Once all skewers have been assembled, feel free to sprinkle them again with freshly ground black pepper and salt before grilling for added flavor.

Grill for about 8 minutes; flip; then grill for an additional 8 minutes, until the chicken is cooked through.