Pound chicken breasts between two sheets of plastic wrap to an even thickness.
Generously salt and pepper both sides of the chicken.
Heat 2 Tablespoons olive oil in skillet over medium heat.
Cook chicken until brown on both sides, turning once, about 6-8 minutes.
While chicken is cooking, dice tomatoes and garlic.
To create a basil chiffonade take 6-8 leaves of basil and roll in a bundle lengthwise. Cut through the bundle, creating ribbons.
When chicken is done (165º Fahrenheit internal temperature), remove to a plate and place tomatoes in the skillet over medium heat until tomatoes break down, about 6 minutes.
Add minced garlic and balsamic vinegar. heat through, about 2 minutes.
Remove tomato sauce from pan and place in a bowl.
Wipe out the skillet with a paper towel.
Place chicken back in the skillet and top each piece of chicken 1 Tablespoon of basil.
Next, layer the tomatoes on top of the chicken and top with mozzarella cheese. Pile it high!
Place under the broiler until cheese is melted , spotty browned and bubbly.
The calories shown are based on the recipe serving 4, with 1 serving being 1 chicken breast. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information.**