In a small bowl, whisk together the fresh orange juice, coconut aminos, and arrowroot powder until the powder is fully dissolved and set aside.
Cut the chicken breast into bite-sized 1-inch cubes and season evenly with sea salt and black pepper.
Heat the toasted sesame oil in a large non-stick skillet or wok over medium-high heat.
Add the chicken to the skillet and sear for 5-6 minutes, turning occasionally, until golden brown and cooked through.
Stir in the minced garlic, grated fresh ginger, and red pepper flakes, sautéing for 1 minute until fragrant.
Add the broccoli florets and 2 tablespoons of water to the pan, cover with a lid, and steam for 2-3 minutes until the broccoli is bright green and tender-crisp.
Remove the lid and pour the orange sauce mixture over the chicken and broccoli.
Toss constantly for 1-2 minutes until the sauce bubbles and thickens into a glossy glaze that coats every piece.
Garnish with thinly sliced green onions and serve immediately.