Heat olive oil in a large skillet over medium high heat.
Season chicken with ½ teaspoon each of salt and 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 the pan and sauté for 1-2 minutes.
Add the garlic and sauté for just 1 minute longer to toast.
Add chicken broth, lemon zest, thyme, balsamic vinegar, and a pinch of salt and pepper to the skillet.
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, if desired.
