Step 1: Preheat your oven to 400°F (200°C). Lightly grease a large baking sheet or line with parchment paper.
Step 2: In a large bowl, combine the cubed chicken, sliced zucchini, halved cherry tomatoes, and sliced red onion.
Step 3: Drizzle with olive oil. Add minced garlic, dried oregano, dried thyme, red pepper flakes (if using), salt, and black pepper. Toss gently to ensure all ingredients are evenly coated.
Step 4: Spread the chicken and vegetable mixture in a single layer on the prepared baking sheet. Ensure there's enough space for even cooking; use two baking sheets if necessary.
Step 5: Bake for 20-25 minutes, or until the chicken is cooked through and the vegetables are tender-crisp. Halfway through cooking, give the mixture a gentle toss.
Step 6: Remove the baking sheet from the oven. Sprinkle the Kalamata olives and crumbled feta cheese over the chicken and vegetables.
Step 7: Return to the oven and bake for another 5-7 minutes, or until the feta is slightly softened and warmed through.
Step 8: Garnish with fresh chopped parsley or dill before serving. Serve hot and enjoy this delicious Mediterranean Chicken Zucchini Bake!