Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Cut the chicken breast into bite-sized 1-inch cubes and place them in a mixing bowl with the broccoli florets.
In a small jar or bowl, whisk together the orange juice, tamari, honey, minced ginger, minced garlic, sesame oil, cornstarch, sea salt, and black pepper until the cornstarch is fully dissolved.
Pour the orange glaze over the chicken and broccoli, tossing thoroughly to ensure every piece is well-coated.
Spread the mixture in a single layer on the prepared baking sheet, ensuring space between the chicken pieces for even browning.
Bake for 18-20 minutes, or until the chicken is cooked through and the sauce has thickened into a sticky glaze.
Remove from the oven and sprinkle with sesame seeds before serving hot.