In a small bowl, whisk together the rice vinegar, soy sauce, hoisin sauce, water, sugar and 1 tablespoon of cornstarch. Set aside until ready to use.
In a large bowl, add the chicken and ¼ cup cornstarch; toss to combine.
Heat oil in a wok or heavy bottom pan to 350˚Fahrenheit. Gently add the chicken and cook for 2-3 minutes on each side, until lightly golden brown. Remove the chicken from the pan and transfer to a cooling rack or paper towel-lined plate.
Discard all but 1 tablespoon of oil. Add in the garlic, ginger, and red pepper flakes. Cook for 20 seconds making sure that it doesn’t brown too much.
Add the chicken, and the sauce into the pan, and stir to combine. Simmer for 1-2 minutes. Garnish with green onions, and sesame seeds. Serve immediately. Enjoy!
