In a large bowl, combine the broth, soy sauce, onions, preserves, oil, garlic, ginger, hot pepper sauce and 1-teaspoon sesame seeds.
Pour 1/3 cup into another bowl for basting; cover and refrigerate.
Pour remaining marinade into a large resealable plastic bag; add chicken. Seal bag and turn to coat; refrigerate for 2-3 hours or overnight, turning occasionally. Drain and discard marinade from chicken.
On metal or soaked wooden skewers, thread chicken, peppers, onion and pineapple.
Grill, uncovered, over medium heat for 6 minutes, basting with reserved marinade.
Grill 5-10 minutes longer or until meat juices run clear, turning and basting frequently.
Sprinkle with remaining sesame seeds and serve.