To a bowl, add the chicken, corn starch, salt, and pepper. Mix so that the chicken is well coated.

On the Instant Pot press on SAUTE (on low) and heat the oil. Add the chicken, and brown it until lightly browned. Remove the chicken from the pot onto a plate and set aside.

Deglaze the pot by adding ¼ cup of water, and with a wooden spoon or a heat resistant spatula scrape off any bits stuck to the bottom of the pot. I recommend discarding the liquid and the chicken cornstarch bits that were stuck to the pot to get a smooth sauce. Switch off the saute setting.

In a bowl, whisk all of the sauce ingredients until well combined, then add them to the Instant Pot and put the chicken back. Add ¼ cup of water to the chicken and sauce, and give everything a good mix.

Secure the lid and set the vent to SEALING. Select the PRESSURE COOK/MANUAL setting and set the cooking time for 5 minutes at high pressure. The Instant Pot will take around 4 minutes to come to pressure and start cooking. When the cooking program ends, quickly release the steam.

Carefully open the lid, and remove the chicken from the pot and set aside.

Press on SAUTE if the sauce is no longer hot, and once the sauce comes to a gentle boil add the cornstarch mixed with water. Whisk until the sauce is thickened (it thickens very quickly). Put the chicken back in, and mix.

Serve over rice, and garnish with chopped green onion.