- 1 pound sourdough bread, cut into 1-inch cubes
- 6 tablespoons olive oil
- 6 tablespoons butter, melted, plus more for the baking dish
- Kosher salt and black pepper
- 2 pounds mixed mushrooms, halved or quartered if large
- 12 shallots, halved or quartered if large
- 6 celery ribs, diced
- 2 cups low-sodium chicken broth
- 4 eggs, lightly beaten
- ½ cup heavy cream
- Heat oven to 425° F. Toss the bread with 3 tablespoons of the oil, 3 tablespoons of the butter, and ½ teaspoon each salt and pepper. Spread out on a rimmed baking sheet. Bake, tossing once, until dry and golden, 15 to 20 minutes; transfer to a large bowl.
- Meanwhile, toss the mushrooms, shallots, and celery with the remaining 3 tablespoons each of oil and butter and season with 2 teaspoons salt and 1 teaspoon pepper. Spread on 2 large rimmed baking sheets and roast, tossing halfway through, until tender and browned in spots, 25 to 30 minutes. Transfer to the same bowl as the bread.
- Whisk the broth with the eggs and cream in a medium bowl. Add to the bowl. Let sit, tossing occasionally, until the liquid is absorbed, 5 to 10 minutes.
- Transfer the stuffing to a buttered 9-by-13-inch baking dish. Cover with foil. Bake until heated through, 30 minutes. Uncover and bake until the top is browned and crisp, 30 minutes more. Serve.
Make Ahead: Refrigerate the stuffing in the dish, unbaked, overnight. Bring to room temperature 30 minutes before baking.