Heat olive oil in a large skillet over medium high heat. Season chicken with ½ teaspoon salt and ½ teaspoon pepper. Add the chicken to skillet and brown on each side, about 2 minutes per side.
Once the chicken has browned, add green beans, and tomatoes to skillet and sauté for 1-2 minutes. Add the garlic and sauté for just 1 minute longer to toast.
Add in chicken broth, lemon zest, thyme, and balsamic vinegar. Lower the heat to medium and cover the skillet. Cook for 5 minutes or until the chicken is cooked through and the beans are just crisp-tender.
Turn off the heat and add the juice of the fresh lemon and serve with Parmesan Cheese if desired.
