Preheat oven to 350°F (175°C).

Remove skin from garlic head without peeling or separating the cloves.

Wrap garlic head in foil.

Bake at 350°F (175°C) for 1 hour.

Let cool for 10 minutes.

Separate garlic cloves, squeezing to extract the inside; reserve half for another use.

In a large pot on medium-high heat, sauté the pancetta for 5 minutes or until crisp.

Remove pancetta and set aside.

Add onion and 1 tablespoon olive oil to drippings in pan.

Sauté for 5 minutes.

Reduce heat to medium-low; cook 25 minutes to brown onion, stirring frequently until tender.

Add vinegar.

Raise oven temperature to 375°F (190°C).

Add garlic pulp, pancetta, squash, broth, thyme, salt, pepper, cannellini beans, and bay leaf to onions, stirring well.

Pulse bread in a food processor about 10 times to make 1 cup dry crumbs.

Combine breadcrumbs, Parmesan cheese, and 1/2 teaspoon olive oil.

Sprinkle breadcrumb mixture over squash mixture.

Cover and bake for 50 minutes or until squash is tender.

Uncover and bake an additional 15 minutes or until topping is browned.

Discard bay leaf.

Sprinkle with parsley.