Rinse rice with water until water runs clear.
Add rice and 1 1/2 cups water (or chicken broth) to the bottom of the instant pot. Spread into a single layer, making sure the rice is covered with water. (It can burn)
Season chicken breast on all sides with salt and pepper, garlic powder and ground ginger. Add chicken to instant pot, nestling it on top of the rice.
Pour 1/4 cup of teriyaki sauce over chicken breast. Secure the lid, and set the valve to sealing.
Cook on manual or pressure cook, high pressure, for 4 minutes (IF using a THICK chicken breast, cook for 6-8 minutes high pressure).
Once the Instant Pot timer beeps, allow the pressure cooker to release naturally for 10 minutes., then quick release the remaining pressure.
While the mixture cooks, heat oil in a large skillet. Once hot, add chopped vegetables and sauté until tender. Add a few spoonfuls of teriyaki sauce to the vegetables and toss to coat.
Open instant pot lid and remove chicken to a cutting board to rest for 5 minutes. Fluff rice with a fork.
Chop chicken, against the grain and add it and the vegetables back to the pot with the rice. Unless you choose to do this beforehand then you can skip this step.
Spoon servings into bowls and top with desired amount of teriyaki sauce.
Garnish with sesame seeds, green onions, and sriracha hot sauce or crushed red pepper flakes, if desired.