To begin, zest and juice one of the lemons, putting the juice and zest in a sauce pan.
Add the oil, onion, basil, rosemary, thyme, oregano, fennel seed, salt, pepper, and garlic.
Heat this over medium heat and cook for about 2 minutes, or until the onions are slightly translucent.
Stir in the tomatoes and allow the mixture to cool to room temperature.
Place your chicken breasts inside a large zip-lock storage bag.
Pour the cooled marinade into the bag, press out the air, and seal the bag shut. "Squish" the bag around to completely coat the chicken and place the bag inside a dish, in case of leaks.
Place the dish in your refrigerator and marinate overnight.
To Prepare the Chicken:
When you are ready to cook the chicken, heat your oven to 375 degrees.
Arrange the chicken in a roasting pan, pouring the marinade over the top.
Cut the remaining lemon into slices and lay the lemon slices on top of the chicken.
Bake for 30-35 minutes, or until the chicken is cooked. Using a meat thermometer, the chicken should read 165 degrees.
Allow the chicken to rest 5 minutes before serving.