Classic Coq Au Vin

1 750-ml bottle French Burgundy or California Pinot Noir

1 large onion , sliced

2 celery stalks, sliced

1 large carrot , peeled, sliced

1 large garlic clove, peeled, flattened

1 teaspoon whole black peppercorn s

2 tablespoons olive oil

1 6-pound roasting chicken , backbone removed, cut into 8 pieces (2 drumsticks, 2 thighs, 2 wings with top quarter of adjoining breast, 2 breasts) Cooking chicken

1 tablespoon olive oil

6 ounces thick-cut bacon slices, cut crosswise into strips

3 tablespoons all purpose flour

2 large shallot s, chopped

2 large garlic cloves, chopped

4 large fresh thyme sprigs

4 large fresh parsley sprigs

2 small bay leaves

2 cups low- salt chicken broth

4 tablespoons ( 1/2 stick) butter

1 pound assorted fresh wild mushroom s (such as crimini and stemmed shiitake)

20 1-inch-diameter pearl onion s, or boiling onions, peeled

Chopped fresh parsley