Pound the chicken: Place each breast between sheets of plastic wrap or parchment. Pound gently with a meat mallet or rolling pin until about 1/2 inch thick. Even thickness means even cooking and fewer dry spots.
Make the marinade: In a bowl, whisk lemon zest, lemon juice, olive oil, garlic, herbs, salt, and pepper. Add Dijon or honey if using.
The mixture should taste bright and well-seasoned.
Marinate: Add chicken to a zip-top bag or shallow dish. Pour the marinade over, turning to coat. Marinate 30 minutes to 2 hours in the fridge. Longer isn’t better with lemon—keep it under 4 hours to protect texture.
Preheat the grill: Heat to medium-high (about 400–425°F).
Clean and oil the grates to prevent sticking. If using a grill pan, heat it until it’s just smoking.
Pat dry (lightly): Remove chicken from the marinade and let excess drip off. Pat lightly with paper towels so it sears, not steams.
Discard used marinade.
Grill: Place chicken on the hottest part of the grill. Cook 4–6 minutes per side, turning once. Look for defined grill marks and clear juices.
Internal temperature should reach 165°F in the thickest part.
Rest: Transfer to a plate and tent loosely with foil for 5 minutes. Resting locks in juices and keeps the meat tender.
Finish and serve: Squeeze fresh lemon over the top, drizzle a little olive oil, and sprinkle extra herbs. Serve with grilled vegetables, rice, or a crisp salad.