The the bowl of a food processor fitted with the "S"blade, or in a blender, add 5 garlic cloves and pulse to chop up. Add the basil, parsley, thyme, zest of one lemon, lemon juice, salt, pepper, and red pepper flakes, if using. Chop until the herbs are minced. Turn the mixer on low and add in the olive oil.

Place chicken breasts in a ziplock bag or container, and pour over 3/4 to all of the marinade, depending on how much chicken you are making. You will have leftover marinade, set it aside for drizzling on the chicken after, or use as a salad dressing. Marinate the chicken for 30 minutes to 2 hours.

Brush grate of the grill with oil to avoid the chicken sticking, and Grill on a charcoal grill until golden and cooked through on both sides, or grill in a grill pan. Oven: Preheat oven to 425 F/200 C. Place marinated chicken on a baking sheet fitted with parchment paper and grill/bake for 20-25 minutes. Thinner chicken breasts will cook faster, so check after 20 minutes for doneness.