Heat gas or charcoal grill. In 2-quart saucepan, mix peanut butter, soy sauce and vinegar until smooth. Stir in sugar and pepper sauce. Cook over medium-high heat about 2 minutes, stirring constantly, until thickened. Place 3/4 cup sauce in small serving bowl to use as dipping sauce.
On each of 6 (12-inch) metal skewers, thread 4 chicken strips and 4 bell pepper pieces alternately, leaving about 1/4-inch space between each piece. Brush chicken and bell pepper with some of the remaining sauce.
Spray kabobs with cooking spray to prevent sticking. Place kabobs on grill over medium heat. Cover grill; cook 5 minutes. Turn kabobs and brush with sauce; cook 2 to 3 minutes longer or until chicken is no longer pink in center. Discard any remaining sauce used for brushing kabobs during grilling. Serve kabobs with reserved sauce for dipping.