Preheat oven to 400°F and line a large baking sheet with parchment paper.
Cut the chicken breast into 1-inch cubes and chop the broccoli and bell peppers into bite-sized pieces.
In a large bowl, whisk together the olive oil, lemon juice, oregano, garlic powder, sea salt, and black pepper.
Add the chicken, broccoli, bell peppers, and rinsed chickpeas to the bowl, tossing thoroughly to coat every piece in the fragrant marinade.
Spread the mixture in a single layer on the prepared baking sheet, ensuring enough space for the vegetables to roast rather than steam.
Bake for 18-22 minutes until the chicken is cooked through and the vegetables are tender with slightly charred edges.
Remove from the oven and finish with an extra squeeze of fresh lemon if desired before serving.