1. Combine chicken stock and eggs. Add toasted sourdough bread cubes.
2. Combine squash, olive oil, kosher salt, and pepper on a baking sheet. Bake at 400° for 15 minutes. Reduce heat to 350°. Cook chopped bacon over medium heat until crisp; remove from pan. Add onion to drippings; sauté until tender. Stir squash, onion, bacon, and sage into bread mixture.
3. Bake stuffing at 350° for 45 minutes in an 11 x 7-inch baking dish coated with cooking spray.