Mix all the ingredients listed under "for the chicken" category, and refrigerate for an hour.
Meanwhile, saute the onions over medium heat, stirring occasionally, until golden brown. Transfer the onions to a paper-towel-lined plate to drain.
Add the sliced bell peppers to the same pan and saute until soft. Transfer to the same paper-towel-lined plate.
Set the oven temperature to broil (high).
Using metal skewers (if using wooden skewers, soak the skewers in water for at least 12 hours), broil the chicken for 5-6 minutes on each side or until done.
While the chicken cooks, prepare 6 paranthas/rotis/tortillas/naans.