Generously salt and pepper both sides of the chicken breasts.

Heat a cast iron skillet over medium-high heat. Drizzle in approximately 2 tablespoons of olive oil and swirl to coat the pan, then place the chicken breasts in the hot pan pretty side down.

Cook until golden brown on the bottom (3-5 minutes) and then flip over and cook until cooked through (another 3-5 minutes) (chicken should reach an internal temperature of 165°F via an instant read thermometer.)

While the chicken is cooking, dice the red onion. Then cut the tomatoes in half, scoop out the seeds, and dice the tomatoes.

When the chicken is cooked removed the breast to a plate to rest. Add the red onion and another tablespoon of olive oil (if the pan is dry.)

Sauté for 2-3 minutes or until the onion is softened and almost translucent. Add the diced tomatoes and sauté for another 1-2 minutes.

Add the balsamic vinegar to the skillet and stir to deglaze the pan and remove from heat.

Add the chicken back to the skillet, scooping the bruschetta topping onto the breasts.

Serve with a drizzle of balsamic vinegar and fresh basil (optional.)