Pat the chicken breast dry and cut into 1-inch bite-sized pieces, then season evenly with sea salt and black pepper.
In a small mixing bowl, whisk together the orange juice, coconut aminos, honey, grated fresh ginger, minced garlic, and arrowroot powder until the powder is fully dissolved.
Heat the avocado oil in a large non-stick skillet or wok over medium-high heat.
Add the chicken pieces to the skillet and sear, stirring occasionally, until golden brown and cooked through, approximately 5 to 6 minutes.
Remove the chicken from the skillet and set aside; add the broccoli florets to the same pan with a tablespoon of water, covering with a lid to steam for 3 minutes until tender-crisp.
Return the chicken to the skillet and pour the orange sauce mixture over the chicken and broccoli.
Stir constantly for 1 to 2 minutes until the sauce thickens into a glossy, translucent glaze that coats everything evenly.
Remove from the heat and stir in the toasted sesame oil.
Serve the orange chicken and broccoli over a bed of warmed cauliflower rice and garnish with sesame seeds.