3/4 cup (1½ sticks) unsalted butter plus more for baking dish
1 pound good-quality day-old white bread, torn into 1-inch pieces (about 10 cups)
2½ cups chopped yellow onions
1½ cups ¼-inch slices celery
2 tablespoons chopped fresh sage
1 tablespoon chopped fresh rosemary
1 tablespoon chopped fresh thyme
2 teaspoons kosher salt
1 teaspoon freshly ground black pepper
2½ cups low-sodium chicken broth, divided
2 large eggs
Step 1
Preheat oven to 250°. Butter a 13x9x2-inch baking dish and set aside. Scatter bread in a single layer on a rimmed baking sheet. Bake, stirring occasionally, until dried out, about 1 hour. Let cool. Transfer to a very large bowl.
Step 2
Meanwhile, melt 3/4 cup butter in a large skillet over medium-high heat. Add onions and celery. Stir often until just beginning to brown, about 10 minutes. Add to bowl with bread. Stir in herbs, salt, and pepper. Drizzle in 1 1/4 cups broth and toss gently. Let cool.
Step 3
Preheat oven to 350°. Whisk 1 1/4 cups broth and eggs in a small bowl. Add to bread mixture and fold gently until thoroughly combined. Transfer to prepared dish, cover with foil, and bake until an instant-read thermometer inserted into the center of dressing registers 160°, about 40 minutes.
Step 4
Remove foil and continue to bake dressing, uncovered, until set and top is browned and crisp, 40–45 minutes longer.
Do Ahead:
Dressing can be baked (before browning) 1 day ahead. Uncover and let cool, then cover and chill. Uncover and bake until top is browned and crisp, 50–60 minutes.