MIX water, barbecue sauce, peanut butter, soy sauce, cilantro and mustard in medium bowl with wire whisk. Refrigerate half of the mixture to use as a dipping sauce. Pour remaining mixture into large resealable plastic bag. Add chicken; seal bag. Shake gently to coat chicken. Refrigerate 1 to 2 hours to marinate.
PREHEAT grill to medium-high heat. Thread chicken onto 12 skewers in ribbon fashion; discard any remaining marinade in bag.
GRILL 5 to 7 min. or until chicken is cooked through. Serve with the reserved dipping sauce.