Preheat your oven to 400°F and line a large sheet pan with parchment paper.
Cut the chicken breast into 1-inch bite-sized pieces and slice the bell pepper into thin strips.
In a small bowl, whisk together the olive oil, lemon juice, lemon zest, dried oregano, garlic powder, sea salt, and black pepper.
Place the chicken, broccoli florets, and bell peppers onto the prepared sheet pan.
Drizzle the lemon-herb marinade over the chicken and vegetables, tossing well to ensure everything is evenly coated.
Spread the ingredients out in a single layer to ensure even roasting and prevent steaming.
Roast for 18-22 minutes, or until the chicken is cooked through and the vegetables are tender and slightly charred.
Remove from the oven and serve immediately, optionally garnishing with fresh parsley.