Pound each breast to an even ½-inch thickness — this is the most important step. Uneven meat means the thin end dries out before the thick end cooks through. Brine if you have time: wet (salt dissolved in water) or dry (salt rubbed directly on meat) both help retain moisture. After brining, pat completely dry — surface moisture kills browning. Season with salt and pepper, brush both sides lightly with olive oil. If using a marinade, minimum 15 minutes, up to overnight in the fridge. Let chicken sit at room temperature for at least 10 minutes before it hits the grill.

Preheat grill to medium-high, targeting 375°F–475°F (374°F–473°F). Once hot, oil the grates with a paper towel dipped in oil held by tongs. Place chicken on the grill and close the lid. Cook the first side without moving it — thin or pounded breasts need 3–5 min, thicker breasts 5–7 min. Chicken is ready to flip when it releases naturally and shows grill marks. Flip once and cook the second side another 3–5 min (thin) or 5–7 min (thick). Total grill time: 10–16 min. Don't press down or flip repeatedly. Check doneness with an instant-read thermometer in the thickest part. Pull at 155°F–165°F (154°F–165°F) and let rest. If a reading seems off on a thin cutlet, confirm visually: juices should run clear and the center should not look translucent. A small slit in the thickest part can help verify.

Pull the chicken off the grill and rest it for at least a few minutes before slicing — this keeps the juices in the meat, not on the cutting board. Confirm internal temp has reached 165°F before serving. If you pulled it at 155–160°F, check that it climbs to 165°F during the rest; if not, return it to the grill briefly. Slice against the grain for the most tender result.