Whisk together the orange sauce ingredients in a bowl. Set aside.
Add the chicken to the Instant Pot. Pour the orange sauce over the chicken. Close the lid, press the Manual button, and set the timer for 5 minutes.
When cooking has finished, naturally release steam for 10-15 minutes. Press the Cancel button and open the lid.
Make a slurry by mixing the corn starch and water in a small bowl. Stir into the chicken mixture.
Press the Sauté button and let the orange chicken cook for a couple minutes until the sauce thickens. Stir in the broccoli and cook for a couple more minutes until tender crisp.
Serve with rice and top with chopped green onion and a sprinkle of sesame seeds.
