1. Heat oven to 425 degrees F. Arrange chicken in shallow roasting pan or heavy jelly-roll pan. With fingertips, separate skin from breast and legs of chicken. Tuck sage leaves under skin. Drizzle chicken with the 1 tablespoon oil; sprinkle with the 1/4 teaspoon salt and the black pepper. Roast 1 to 1-1/4 hours or until a meat thermometer inserted in thigh registers 180 degrees F.
2. For the cabbage, heat a 12-inch skillet over medium-high heat. Add pancetta and cook 2 to 3 minutes, stirring, until browned and crisp. Transfer with slotted spoon to paper towels. Add the 2 tablespoons oil; stir in fennel and onions (and ham, if using); cook 3 to 4 minutes or until softened. Reduce heat to medium. Add cabbage, the 1/4 cup chicken broth, the 1/2 teaspoon salt and red pepper. Cover and cook 12 to 15 minutes or until tender, stirring once. Add vinegar; stir and transfer to serving bowl. Cover and keep warm.
3. Transfer chicken to serving platter; cover and keep warm. Pour drippings into measuring cup; skim fat. Add the 1/2 cup chicken broth to cup; whisk in flour. Add to roasting pan and bring to boil, scraping up browned bits; boil 1 minute. Carefully pour gravy through a sieve into gravy bowl. Serve chicken with gravy and Cabbage. Garnish with fresh sage leaves, if desired. Makes 6 servings.