Cook the rice. Make your rice first so it’s hot and ready. Keep it covered to stay fluffy.
Make the teriyaki base. In a bowl, whisk soy sauce, mirin, honey (or brown sugar), rice vinegar, garlic, and ginger.
Taste and adjust sweetness or saltiness.
Prep the chicken. Pat chicken dry and cut into bite-size pieces or thin strips. Season lightly with salt only if using low-sodium soy.
Sear the chicken. Heat oil in a large skillet over medium-high. Add chicken in a single layer.
Cook 5–7 minutes, stirring once or twice, until cooked through and lightly browned. Remove to a plate.
Cook the veggies. In the same pan, add a splash of oil if needed. Add broccoli, carrots, and bell pepper.
Stir-fry 3–4 minutes until crisp-tender. Push to the sides of the pan.
Thicken the sauce. Pour the teriyaki base into the center of the pan. Bring to a simmer.
Stir in the cornstarch slurry and cook 30–60 seconds until glossy.
Combine. Return chicken to the pan. Toss everything in the sauce until evenly coated. If too thick, loosen with a splash of water.
If too thin, simmer another minute.
Assemble bowls. Spoon rice into bowls. Top with chicken and veggies. Sprinkle with sesame seeds and green onions.
Add heat if you like.
Serve. Enjoy immediately while hot and saucy.