Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Slice the zucchini into half-moons and chop the bell peppers into bite-sized pieces.
Cut the chicken breast into uniform 1-inch cubes to ensure even cooking.
In a large mixing bowl, whisk together the extra virgin olive oil, lemon juice, minced garlic, dried oregano, sea salt, and black pepper.
Add the chicken cubes and chopped vegetables to the bowl, tossing thoroughly until everything is well-coated in the herb marinade.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the pieces are not overcrowded.
Roast in the oven for 20-25 minutes, or until the chicken is cooked through and the vegetables are tender with slightly caramelized edges.
Remove from the oven and let cool slightly before portioning into meal prep containers.