Place chicken in a large pan that will allow it to marinate without leaking over the sides. I usually use a casserole dish or sheet cake pan.
Squeeze 1/4 of the lemon juice onto each chicken breast using the entire lemon by the time you have covered all the chicken breast. I did this on one side.
Next, sprinkle with black pepper and rosemary. At this point I use the amount I feel comfortable with making sure that the chicken breast is coated well with pepper and rosemary.
Next add a little crushed garlic to each chicken breast.
Let this marinate for about 4 hours.
Grill these on the grill, flipping occasionally until no longer pink in the middle on medium heat. These typically take 20-30 minutes.