Cook the brown rice according to package instructions and set aside.
In a small bowl, whisk together the tamari, rice vinegar, honey, arrowroot powder, minced ginger, minced garlic, and red pepper flakes to create the sauce.
Cut the chicken breast into bite-sized cubes.
Heat the avocado oil in a large skillet or wok over medium-high heat.
Add the chicken to the skillet and sauté until golden brown and cooked through, approximately 5-7 minutes.
Add the broccoli florets to the pan with a tablespoon of water, then cover with a lid for 2 minutes to steam until tender-crisp.
Remove the lid and pour the sauce over the chicken and broccoli mixture.
Stir constantly for 1-2 minutes until the sauce thickens into a glossy glaze that coats the ingredients.
Remove from heat, drizzle with sesame oil, and serve immediately over the cooked brown rice.