Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Cut the chicken breast into uniform 1-inch cubes and chop the broccoli and red bell pepper into bite-sized pieces.
In a small mixing bowl, whisk together the tamari, honey, sesame oil, grated fresh ginger, and minced garlic until well combined.
Place the chicken cubes, broccoli, and bell peppers onto the prepared baking sheet, drizzle with olive oil, and season with sea salt and black pepper.
Toss the ingredients on the tray to ensure an even coating of oil, then spread them out in a single layer to ensure even roasting.
Roast in the oven for 15 to 18 minutes, or until the chicken is cooked through and the vegetables are tender with slightly charred edges.
Remove the tray from the oven, drizzle the tamari glaze over the hot chicken and vegetables, and toss thoroughly to coat before serving.