2 1/2 cups young Tuscan red wine, also known as "vino novello"
1 cup whole chestnuts, peeled (see note)
4 (8-ounce) white Pekin duck breasts, skin on and excess fat trimmed
Salt and freshly ground pepper
2 pounds Brussels sprouts, trimmed of outer leaves and sliced into three pieces from stem to tip
1/4 cup balsamic vinegar