Preheat oven to 400°F and line a large sheet pan with parchment paper for easy cleanup.
Cut the chicken breast into 1-inch cubes and chop the broccoli, bell pepper, and zucchini into bite-sized pieces.
In a small bowl, whisk together the olive oil, lemon juice, lemon zest, minced garlic, oregano, thyme, salt, and pepper.
Place the chicken and vegetables on the prepared sheet pan and pour the lemon-herb marinade over them, tossing well to ensure everything is evenly coated.
Spread the mixture into a single layer, ensuring the chicken pieces are not overlapping to allow for even browning.
Roast for 20-25 minutes, or until the chicken is cooked through and the vegetables are tender and slightly caramelized at the edges.