Put chicken and green onion pieces onto skewers. Set aside
Heat the grill very hot. Grease the grate with some oil and place the chicken skewers. Grill until the chicken is cooked through, turning once or twice.
Meanwhile, mix soy sauce, pineapple juice, rice wine, sugar, garlic, ginger, sesame oil, pepper, and cornstarch in a small skillet. Boil until thickened.
Brush the sauce over the chicken skewers and sprinkle toasted sesame seeds over. Serve warm.