The first step in creating the perfectly grilled chicken breasts is to defrost your chicken if it happens to be frozen. Fresh chicken is always nicer, but can be costly. If you are using fresh chicken then you can skip this step because your chicken is already ready to go.
Next you are going to want to trim off any excess fat, cartilage or uneven pieces of chicken. We are going to attempt to make our chicken one uniform thickness. Save the thinner pieces and throw them in a freezer bag; you can always turn these into stir fry meat or make stews with them.
Next, cut thin crosswise slits in the chicken breast the entire length of the chicken being extremely careful not to cut all the way through. By creating these little slits we are allowing the marinade to more easily penetrate the chicken which will help keep the chicken juicy; plus it looks kind of cool!
Marinating the meat is going to be our next step in our chicken grilling tutorial. If you prefer to buy a marinade, aim for something that is oil based as the oil helps seal in the juiciness of the chicken. The other ingredients should be at least partially acidic, like lemon juice or vinegar based. If you are making the marinade yourself make the oil to acidic ingredients ratio is 2:1. You can feel free to add in other ingredients too such as garlic, onions, ginger, and mustard amongst other things. Just make sure you avoid salt in your marinade as it will really dry your chicken out. If you want to add something salty, add it to the chicken when you are ready to eat it.
Next, place your chicken in the marinade and let it sit for at least a few hours. Most people will marinade their chicken for 6-8 hours or more to make sure the marinade flavor really permeates the chicken tissue. Make sure you set some marinade aside to be brushed on your meat while cooking. If you plan on using the marinade you had your chicken sitting in all day, make sure you don't apply any of it on your chicken for the last five minutes it is cooking as you will want to kill off any random bacteria.
Our next step is to cook up those chicken breasts! Set your grill to medium-high temperature and when it is preheated, place your chicken breasts on the grill. Grill your chicken until the top side of the chicken begins to turn an opaque color (as opposed to pink). Once the top of the chicken begins to change color, flip the meat and apply a little more marinade to the top of those breasts. Once both sides of the chicken are nicely browned, press down on the chicken with your fingers, the meat should be firm but not hard, if it is hard you probably over cooked it and may have risked drying it out. If you have a meat thermometer handy, use it to see if the center of the chicken is done cooking. Chicken that is fully cooked should be 165 degrees F and should be cooked all the way through with no pink slimy texture remaining inside.
Once you made sure the chicken is cooked all the way through, pull it off the grill and serve it up with a salad or a freshly baked potato and sit back and enjoy your fresh juicy chicken breasts.