As posted on Boston.com and adapted from Cheryl Jost

Ingredients:

• 1/4 cup balsamic vinegar
• 3 tablespoons olive oil
• 1 clove garlic, finely chopped
• 1/4 cup chicken stock
• Salt and pepper, to taste
• 4 skinless, boneless chicken breast halves
• 6 sun-dried tomatoes (oil-packed)
• 1/2 pound fresh mozzarella, sliced about 1/2 inch thick
• Handful of fresh basil leaves

1. In a medium bowl, combine the vinegar, 2 tablespoons of the olive oil, garlic, stock, salt, and pepper. Add the chicken, stir well, and cover with plastic wrap. Refrigerate for 30 minutes or for up to 2 hours.
2. Remove the chicken from marinade. With a sharp knife, cut horizontal slits in one side of each breast to form pockets. Don’t cut all the way through.
3. With your hand or the flat side of a knife, slightly flatten four of the sun-dried tomatoes. Chop the remaining 2 tomatoes. Into the pocket of each breast, insert a sun-dried tomato, a slice or two of mozzarella, some chopped sun-dried tomato, and a few basil leaves. Pinch the edges of each breast to close them.
4. In a large skillet over medium heat, heat the remaining 1 tablespoon olive oil. When the oil is hot, add the breasts. Cook, turning once, for 7 minutes on a side or until cooked through.
5. Transfer the chicken to a cutting board. Slice them and arrange each one on a plate, fanning out the slices.