1/2 cup good olive oil
1/2 cup good red wine vinegar
1 1/2 cups large pitted prunes, such as Sunsweet
1 cup large green olives, pitted, such as Cerignola (see tip)
1/2 cup capers, including the juices (3 1/2 ounces)
6 bay leaves
1 1/2 heads of garlic, cloves separated, peeled, and minced (see tip)
1/4 cup dried oregano
Kosher salt and freshly ground black pepper
2 (4-pound) chickens, backs removed and cut in 8 pieces
1/2 cup light brown sugar, lightly packed
1 cup dry white wine, such as Pinot Grigio