In a medium bowl, whisk together soy sauce, brown sugar, honey, sesame oil, minced garlic, grated ginger, and rice vinegar to create the teriyaki marinade.

Place the chicken chunks in the marinade, ensuring all pieces are well-coated. Cover the bowl and refrigerate for at least 30 minutes, or up to 2 hours for better flavor.

While the chicken is marinating, soak wooden skewers in water to prevent burning during cooking.

After marinating, thread the chicken pieces onto the soaked wooden skewers, leaving a small gap between each piece for even cooking.

Preheat grill or stovetop grill pan over medium-high heat. Lightly grease the grill with a bit of sesame oil to prevent sticking.

Grill the chicken skewers for about 4-5 minutes per side, or until the chicken is fully cooked and has nice grill marks. Brush the skewers with leftover marinade during grilling for extra flavor, but stop brushing in the last minute of cooking to ensure food safety.

To make the teriyaki glaze, combine the cornstarch and water in a small bowl to create a slurry. Heat the leftover marinade in a saucepan over medium heat, and stir in the cornstarch slurry. Simmer for 2-3 minutes until the sauce thickens.

Once the chicken skewers are cooked, drizzle the thickened teriyaki glaze over the skewers or serve it on the side for dipping.

Garnish with sesame seeds and chopped green onions, if desired. Serve immediately.