Using a small, sharp knife, cut into the fullest side of each chicken breast, making a deep incision into the meat to form a pocket across each breast. Stuff some cheese into each breast, then season liberally with pepper and gingerly with salt.
Cut the watermelon into 1/4-inch-thick slices, then again into large bite-size pieces. Gently slice the tomatoes in a similar shape. If you are using smaller tomatoes, halve or quarter them.
Peel the onion and quarter it lengthwise. Thinly slice the onion and combine it with the watermelon, tomatoes, parsley and mint. Dress the salad with lots of salt and pepper and about 4 tablespoons EVOO.
Heat about 2 tablespoons EVOO in large skillet over medium-high heat. Cook the chicken for 6 minutes on each side. For outdoor or grill pan preparation, coat the chicken with about 2 tablespoons EVOO, season with salt and pepper, then grill for 12 minutes over medium-high heat.
Let the chicken rest for 5 minutes, then slice it in wide slices on an angle and fan out the pieces on plates. If using, garnish the chicken with some balsamic drizzle. Serve with large portions of salad and garnish with pita chips or crisps alongside.
This is one of many “Yum-o!” recipes – it’s good and good for you. To find out more about Yum-o!, Rachael’s nonprofit organization, go to www.yum-o.org.