In a small bowl, mix together all the marinade ingredients.
In a large resealable plastic bag, place the marinade, chicken, red and green bell peppers, and onion wedges. Seal and mix to coat. Refrigerate 4 to 24 hours.
When ready to cook, preheat grill for medium-high heat.
Discard marinade and thread the meat and vegetables onto skewers, leaving a small space between each item.
Lightly oil the grill grate. Grill skewers for 10 minutes, turning as needed, or until meat is cooked through and vegetables are tender.