Pat your chicken dry on a plate and season it on both sides with salt and pepper. Heat a large frying pan on medium high. Add a couple tablespoons of oil and let it get warm. Once hot, brown the chicken well on both sides, about 8 to 10 minutes total; it’s not going to fully cook through right now, and that’s fine. Transfer it back to a plate to rest. Add more oil to the pan, if needed. Add garlic and ginger and cook, stirring, for 1 minute. Add soy sauce, vinegar(s), and sugar and stir to scrape up anything stuck in the pan. Bring sauce ingredients to a simmer, 1 minute. Return the chicken to the pan and cook in the sauce, turning once or twice, until the chicken is cooked through, about 5 minutes more. The sauce will reduce as the chicken cooks and get a bit syrupy. Transfer chicken to a serving platter and pour the sauce remaining in the pan over. Sprinkle with sesame seeds and/or scallion and eat right away, preferably with some chili crisp.
From Deb
If using chicken breast cutlets, I often pound or slice them thinner so that they cook faster. I really love using a mixture of (unseasoned) rice vinegar and black vinegar (here are good explainers on both kinds) but use whatever you have. The glaze will be lighter in color with only rice vinegar. To ensure this dish is gluten-free for anyone who needs it to be, check that your tamari or soy sauce is labeled as such.