Coat The Chicken. In a medium bowl or container, combine diced chicken with 2 Tbsp. cornstarch and 1 1/2 Tbsp. tamari. Toss with a fork to coat well.

Cook The Chicken. In a large skillet, heat 1 Tbsp. avocado oil over medium-high heat. Working in batches, add chicken pieces to the pan (they shouldn't be touching) and cook 3-4 minutes on the first side and 1-3 minutes on the second side to cook through. (They should be fully opaque and have no pink inside). Remove cooked chicken to a clean plate and repeat with remaining chicken until add chicken is cooked, adding more oil to the pan as needed.

While The Chicken Cooks, Make The Sauce. In a bowl or liquid measuring cup, combine water, tamari, syrup or honey, vinegar, toasted sesame oil, garlic, ginger, and red pepper flakes (if using). Whisk to combine.

Make The Slurry. In a small bowl, whisk together 1 Tbsp cornstarch with 1 Tbsp water to make a cornstarch slurry.

Cook The Sauce. When the chicken is fully cooked, reduce the heat in the pan to medium-low. Add cornstarch slurry to the sesame sauce mixture and whisk to combine (it'll now look a bit milky). Pour sauce mixture into the warm pan and whisk over medium-low heat 3-5 minutes, or until the sauce is bubbling, thickened, and more translucent. (You should start to be able to see the path of your whisk in the sauce).

Heat Through. Return cooked chicken to pan and coat with the sauce to heat through. Sprinkle with sesame seeds and serve warm! Store leftovers in an airtight container in the fridge 3-4 days. Keep in mind the sauce will gel and thicken when chilled. You can thin out leftover sauce by warming it up with a little drizzle of water.