Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Dice the chicken breast, zucchini, and red bell pepper into uniform 1-inch pieces to ensure even cooking.
In a large mixing bowl, whisk together the extra virgin olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Add the diced chicken, broccoli florets, zucchini, and bell peppers to the bowl, tossing thoroughly until every piece is well-coated in the herb dressing.
Spread the mixture onto the prepared baking sheet in a single layer, making sure not to overcrowd the pan so the vegetables roast rather than steam.
Roast for 20 to 25 minutes, or until the chicken is cooked through and the vegetables are tender with slightly caramelized edges.