In a medium sized bowl, combine the Italian salad dressing, thyme, Italian seasoning, lemon juice, and garlic cloves. Stir to combine.
Reserve 1/4 cup of the marinade (to be used for basting later).
Transfer the mixture to a large Ziploc bag. Add the chicken. Close the bag, and place in the fridge to marinate for 3-5 hours, or overnight.
Pull the chicken out of the fridge. Let sit at room temperature for 15 minutes. Remove the chicken from the marinade and discard the marinade.
Heat a grill to 375°F - 400°F. Place the chicken breasts on the grill. **Cook the first side for 5 minutes. Flip and immediately thoroughly baste each chicken breast with the 1/4 cup of reserved marinade.
Close the grill lid and cook for an additional 5-6 minutes or until inside temperature reaches 155°F-160°F.
Remove from the grill and place the meat on a plate, tent with foil to keep the meat warm. Let rest for 5 minutes before serving.
Notes
* You will need an instant read thermometer for this part. The meat continues to cook a few minutes after removing it from the grill. If you cook it until the temp reads 160°, your meat will be fully cooked by the time it's on your table. AND it will be juicy and so delicious!! **If you find your grill is at 400° a majority of the time, you may only need to cook each side for 4.5- 5 minutes. Be sure to check so that your meat isn't dry and overcooked.