Preheat oven to 375 degrees F (if you choose to bake your chicken rather than grill). Sprinkle some salt and pepper over top, cover and bake for about 35 to 40 minutes (depending on the size of your breasts) until juices run clear.

Meanwhile, combine chopped tomatoes, garlic, onion, olive oil, balsamic vinegar, sea salt and basil in a bowl. Refrigerate until chicken is ready to be served and spoon over top of the chicken.