- 2 sweet potatoes, peeled and cut into 2-inch pieces
 - 1 tablespoon olive oil
 - salt and pepper to taste
 - 2 skinless, boneless chicken breast halves
 - 1/2 cup balsamic vinegar
 - salt and ground black pepper to taste
 - 1/2 cup balsamic vinegar
 
- Preheat oven to 400 degrees F (200 degrees C).
 - Place the potatoes on a baking sheet; drizzle olive oil over potatoes and season with salt and pepper.
 - Place the chicken breasts in a baking dish. Pour 1/2 cup of balsamic vinegar over the breasts; season with salt and pepper. Cover with aluminum foil.
 - Place the potatoes in the preheated oven and bake for 10 minutes; place the dish with the chicken in the oven and cook both the potatoes an chicken another 20 minutes; flip both the potatoes and chicken; reduce the oven heat to 350 degrees F (175 degrees C). Bake another 20 minutes.
 - Pour 1/2 cup of balsamic vinegar into a small saucepan and place over medium heat. Cook until reduced to about 1/4 cup. Place the chicken breasts atop the potatoes; drizzle with the reduced balsamic vinegar to serve.