In a large bowl, combine the olive oil, minced garlic, lemon juice and zest, oregano, thyme, salt, and pepper. Whisk together to form a marinade.
Add the chicken breasts to the marinade, ensuring they are well-coated. Cover and refrigerate for at least 30 minutes or up to 2 hours for more flavor.
Preheat your grill or a skillet over medium-high heat. Remove the chicken from the marinade, allowing excess marinade to drip off.
Grill or cook the chicken for about 6-7 minutes per side, or until the internal temperature reaches 165°F (75°C) and the chicken is cooked through.
In the last couple of minutes of cooking, sprinkle the crumbled feta cheese, cherry tomatoes, and kalamata olives over the chicken to warm them slightly.
Remove the chicken from the heat, let it rest for 5 minutes, then slice it.
Serve the chicken drizzled with the remaining marinade and topped with fresh parsley.
Notes
Marinate the chicken for longer for enhanced flavor.