Preheat your oven to 375°F (190°C).
Lightly grease a 9×13-inch baking dish.
In a saucepan over medium heat, combine soy sauce, honey, rice vinegar, sesame oil, garlic, and ginger.
Bring to a gentle simmer.
In a small bowl, mix cornstarch with water until smooth.
Slowly whisk the slurry into the sauce and cook until thickened (2-3 minutes).
Remove from heat.
In a large bowl, combine cooked rice, chicken, broccoli, bell pepper, carrots, and half of the green onions.
Pour most of the teriyaki sauce over the mixture and stir until evenly coated.
Transfer everything into the prepared baking dish.
Drizzle remaining sauce over the top.
Cover with foil and bake for 20 minutes.
Remove foil and bake an additional 5-10 minutes until heated through and slightly golden on top.
Sprinkle with sesame seeds and remaining green onions before serving.
