Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Cut the chicken breast into even 1-inch chunks and toss them in a bowl with avocado oil, sea salt, and black pepper.
Spread the chicken and broccoli florets across the baking sheet in a single layer, ensuring they aren't crowded.
Bake for 15 to 18 minutes, or until the chicken is cooked through and the broccoli edges are slightly charred.
While the chicken bakes, whisk together the orange juice, coconut aminos, rice vinegar, honey, minced ginger, minced garlic, and arrowroot powder in a small saucepan.
Place the saucepan over medium heat and simmer for 3 to 5 minutes, whisking constantly until the sauce thickens into a glossy glaze.
Once the chicken and broccoli are done, transfer them to a large bowl and pour the warm orange glaze over the top, tossing gently to coat every piece.
Serve the orange chicken and broccoli over the cooked brown rice and garnish with a sprinkle of sesame seeds.