Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Cut the chicken breast into 1-inch bite-sized cubes and place them in a large mixing bowl along with the broccoli florets.
In a small bowl, whisk together the fresh orange juice, orange zest, coconut aminos, toasted sesame oil, arrowroot powder, minced ginger, and minced garlic until smooth.
Pour the orange sauce over the chicken and broccoli, sprinkle with sea salt and black pepper, and toss thoroughly to ensure every piece is well-coated.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the pieces aren't too crowded so they roast rather than steam.
Bake for 18 to 20 minutes, or until the chicken is cooked through and the sauce has thickened into a glossy glaze.
Remove from the oven and serve immediately over the warm cooked brown rice.
Garnish with sesame seeds for a final touch of crunch and flavor.