Place the inner pot inside the Instant Pot. Add the chicken, soy sauce, ginger, garlic, water, light brown sugar, and vinegar.
Close and lock the Instant Pot lid. Make sure the steam release handle is turned to Sealing. Press Pressure Cook, pressure level High, and set time to 10 Minutes.
Once the time is up, press Cancel and turn the steam release handle to Venting. Once all the pressure has been released, open the lid.
Remove the chicken and shred with a fork.
Pres Saute and add the dissolved corn starch. Stir constantly until thickened.
Strain the teriyaki sauce. Mix with the shredded chicken and toasted sesame seeds.
Serve with chopped green onion and rice or other side dish.