Start by preheating your oven to 400ºF. This step is crucial as it ensures the casserole will cook evenly.
Next, take a 9x13-inch pan and spray the bottom with olive oil spray. This will prevent the food from sticking and help with cleanup.
Place the chicken breasts in the center of the pan, arranging them so they have some space around them for the vegetables.
Add the vegetables around the edges of the chicken, creating a colorful display. This not only looks pretty but allows the flavors to meld together.
Spray the chicken and vegetables lightly with olive oil. This will enhance the roasting process and add a bit of crispiness.
Sprinkle salt and pepper over the top of the chicken and vegetables. This basic seasoning is key to enhancing the dish's overall flavor.
Pour about 3/4 to 1 cup of teriyaki sauce over the chicken. Make sure it covers the chicken well, allowing it to soak in during cooking.
Cover the pan with foil and place it in the preheated oven. Bake it for 25 minutes, or until the chicken is cooked through and reaches an internal temperature of 165 degrees. You'll know it’s done when the juices run clear.
Once done, remove the pan from the oven and carefully take out the chicken. Let it rest for about 5 minutes. This allows the juices to redistribute, making the chicken tender.
While the chicken rests, stir the vegetables and return them to the oven for an additional 10 minutes, or until they become fork-tender.
Now, shred the chicken into bite-sized pieces and add it back into the pan with the cooked rice. Drizzle an extra 1/4 to 1/2 cup of teriyaki sauce over the mixture and gently stir to combine everything.
Finally, return the casserole to the oven for another 5 minutes to heat through. Serve the dish warm, alongside extra teriyaki sauce for drizzling, and garnish with sesame seeds and sliced green onions if desired.
