Cut the chicken breast into bite-sized cubes and toss in a bowl with arrowroot powder until lightly coated.
In a small jar, whisk together the coconut aminos, rice vinegar, honey, minced ginger, minced garlic, toasted sesame oil, and red pepper flakes to create the sauce.
Heat the avocado oil in a large skillet or wok over medium-high heat.
Add the chicken to the skillet and cook for 5-6 minutes, turning occasionally, until golden brown and cooked through.
Remove the chicken from the pan and set aside.
Add the broccoli florets and sliced red bell pepper to the same skillet with a splash of water, covering for 2 minutes to steam-soften.
Return the chicken to the pan and pour the prepared sauce over the mixture.
Stir-fry for 1-2 minutes until the sauce thickens into a glossy glaze and coats the chicken and vegetables.
Garnish with sesame seeds and sliced green onions before serving.