01 - Preheat the oven to 400°F. Lightly coat a large baking dish with a thin layer of olive oil to prevent sticking.
02 - In a small mixing bowl, whisk together the olive oil, minced garlic, lemon zest, lemon juice, dried oregano, fresh thyme leaves, salt, and black pepper until well combined.
03 - Place the chicken breasts in the prepared baking dish in a single layer. Brush generously with half of the marinade mixture, ensuring even coverage on all sides.
04 - Scatter the sliced zucchini, bell pepper strips, red onion, and halved cherry tomatoes around and over the chicken pieces. Drizzle the remaining marinade evenly across all the vegetables.
05 - Bake uncovered for 25 minutes, allowing the chicken to begin cooking through and the vegetables to soften and release their juices.
06 - Remove the dish from the oven. Scatter the baby spinach leaves over the top and sprinkle the crumbled feta cheese evenly across the entire dish. Return to the oven and bake for an additional 8 to 10 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender.
07 - Remove from the oven and let rest for 2 to 3 minutes. Garnish with freshly chopped basil and serve hot.