Preheat the Oven:
Preheat to 375°F (190°C). Lightly grease a baking dish large enough to fit the peppers.
Cook the Chicken:
Heat olive oil in a skillet over medium heat. Add diced chicken, onion, and garlic. Cook for 5–7 minutes until golden and cooked through.
Make the Teriyaki Sauce:
In a small bowl, whisk soy sauce, honey, rice vinegar, and ginger. Pour over the chicken. Simmer for 2–3 minutes, then add the cornstarch slurry. Stir until the sauce thickens.
Combine Filling:
Add cooked rice and pineapple chunks to the skillet. Stir well to combine all flavors.
Stuff the Peppers:
Spoon the teriyaki chicken mixture evenly into each hollow bell pepper. Place in the prepared baking dish and top with cheese if desired.
Bake:
Bake for 25–30 minutes or until the peppers are tender and slightly caramelized.
Serve and Enjoy:
Garnish with sesame seeds and green onions before serving.