1. Create the marinade. In a small saucepan over medium heat, whisk together balsamic vinegar, pineapple juice, brown sugar, sesame oil, garlic powder, ground ginger and pepper. Bring to a simmer.
2. Whisk together cold water and corn starch until combined. Slowly add cornstarch mixture into the marinade and combine.
3. Allow to simmer and mix occasionally for 3-4 minutes until marinade thickens. Remove from heat and set aside to cool.
4. Place diced chicken in a large plastic zip top bag or a bowl and add half of the marinade and toss to coat the chicken. Cover and refrigerate up to 4 hours and at least one hour.
5. Soak your wooden skewers in water for at least 30 minutes prior to using. If you are using metal skewers, you can skip this step.
6. Preheat oven broiler. Line baking sheet with a baking parchment or aluminum foil.
7. Separate chicken into 4 equal servings. Create the kabobs by alternately threading chicken, peppers, onion, and pineapple onto skewers. Brush sesame oil on vegetables. Each serving is two skewers of meat and vegetables so you are making 8 skewers.
8. Arrange kabobs in individual layer on baking sheet. Place under broiler and every 5 minutes turn and baste with remaining marinade until chicken is done. About 20 minutes.