Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Chop the broccoli into small bite-sized florets and slice the red bell pepper into thin strips.
Pat the chicken breast dry with a paper towel and slice it into even 1-inch strips to ensure even cooking.
In a large mixing bowl, whisk together the olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Add the chicken strips and chopped vegetables to the bowl, tossing thoroughly until every piece is coated in the herb marinade.
Spread the chicken and vegetables in a single layer on the prepared baking sheet, ensuring they are not overcrowded so they roast rather than steam.
Roast in the center of the oven for 18-20 minutes, or until the chicken is cooked through and the vegetables are tender with slightly charred edges.
Remove from the oven and serve immediately while hot, garnishing with extra lemon zest if desired.