In between two pieces of plastic wrap, pound chicken breasts to 1/2" thick. (Mine were large, so I cut them in half). Salt and pepper both sides.
Heat oil in saucepan on medium-high. Brown chicken on both sides. Reduce heat to medium-low and add garlic.
Cook until garlic is tender, being careful not to burn it. Add broth, balsamic and Truvia. Turn heat up to medium-high and simmer for 10-12 minutes, covered until chicken is cooked through.
Preheat broiler. Line baking sheet with parchment. Place each chicken piece on baking sheet. Place a sprig of basil on top of each breast then cover with a slice of mozzarella.
Broil until cheese is slightly melted. Add tomato slice on top. Heat again until tomato is warm and cheese is melted. Serve as is or with a little extra sauce from the pan drizzled on top. Enjoy!