If marinating, follow marinating instructions before grilling. 

Preheat the grill on HIGH heat for 12 minutes. 

While the grill is preheating, pound the chicken breasts to an even thickness all over, approximately 1 inch. Salt and pepper to taste.

After preheating but before placing the chicken on the grill, turn the grill down to MEDIUM heat. Place the chicken on the grill over direct heat.

Cook for 9 minutes, flipping halfway though. 

At the 9 minute mark, use a meat thermometer to check the internal temperature at the center of the chicken breast. Pull the chicken off of the grill as soon as it hits 165°.

Allow the chicken to rest on a plate for 5 minutes before serving.