1. Prepare the Chicken Breasts: If your chicken breasts are very thick (over 1 inch), pound them lightly to an even thickness of about 3/4 inch. Place each chicken breast between two pieces of plastic wrap or in a large zip-top bag and gently pound with a meat mallet or the flat side of a rolling pin. This ensures even cooking.

2. Whisk Together the Marinade: In a medium bowl, combine the olive oil, fresh lemon juice, chopped fresh parsley, chopped fresh oregano, chopped fresh thyme, minced garlic, salt, and black pepper. Whisk everything together until well combined. The marinade should look slightly emulsified and fragrant with the herbs and lemon.

3. Marinate the Chicken: Place the prepared chicken breasts into a large zip-top bag or a shallow dish. Pour the lemon herb marinade over the chicken, ensuring all pieces are well coated. Seal the bag or cover the dish and refrigerate for at least 30 minutes, or up to 2 hours. For the best flavor, aim for at least an hour.

4. Preheat the Grill: While the chicken is marinating, preheat your outdoor grill to medium-high heat (around 400-450 F / 200-230 C). Clean the grill grates thoroughly with a wire brush to prevent sticking. Lightly oil the grates by dipping a paper towel in a little vegetable oil and carefully wiping it over the hot grates using tongs.

5. Grill the Chicken: Remove the chicken from the marinade, allowing any excess to drip off (discard the remaining marinade). Place the chicken breasts directly on the preheated, oiled grill grates. Close the lid and cook for 6-9 minutes per side, depending on the thickness of the chicken. You should see nice grill marks forming.

6. Check for Doneness and Rest: The chicken is cooked when it reaches an internal temperature of 165 F (74 C) as measured with an instant-read meat thermometer inserted into the thickest part of the breast. Once cooked, transfer the chicken to a clean cutting board or platter.

7. Rest Before Serving: Tent the chicken loosely with aluminum foil and let it rest for 5-10 minutes before slicing or serving. This resting period allows the juices to redistribute throughout the meat, resulting in a much juicier and more tender chicken.

8. Garnish and Serve: Garnish with fresh lemon wedges and a sprinkle of fresh parsley, if desired. Serve immediately and enjoy your delicious Lemon Herb Grilled Chicken!