Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Cut the chicken breast into bite-sized pieces and chop the bell pepper and zucchini into similar sizes to ensure even cooking.
In a small mixing bowl, whisk together the extra virgin olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Place the chicken pieces, broccoli florets, bell pepper, and zucchini onto the prepared sheet pan.
Drizzle the lemon-herb marinade over the chicken and vegetables, then toss thoroughly with your hands or tongs to coat every piece.
Spread the mixture out into a single layer, making sure not to overcrowd the pan so the vegetables roast rather than steam.
Bake for 18 to 22 minutes until the chicken is fully cooked through and the vegetables are tender with slightly charred edges.
Remove from the oven and serve immediately while hot, perhaps with a final squeeze of fresh lemon for extra brightness.