Step 1

Preheat oven to 350°F. Brush a 2-to-3-quart dish (see cook's note). Shingle bread on a rimmed baking sheet in a single overlapping layer. Bake, flipping once, until golden and very dry, 25 to 30 minutes. When cool enough to handle, cut into approximately 1-inch pieces; transfer to a large bowl.

Step 2

Increase oven temperature to 425°F. Heat butter in a large skillet over medium. When it melts and foam subsides, add onion and celery; season generously with salt and pepper. Cook, stirring occasionally, until vegetables are tender but no color has developed, 10 to 12 minutes. Stir in fresh and dried herbs and cook just until fragrant, about 30 seconds. Transfer to bowl with bread mixture, along with cranberries and 1 cup stock. Season and toss to combine. Whisk remaining 1/2 cup stock with eggs. Pour over bread mixture and gently stir to combine. Reserve 3 cups stuffing for turkey-breast roulade, and transfer remainder to prepared dish. Cover with parchment-lined foil.

Step 3

Bake 30 minutes; uncover and reduce temperature to 350°F. Continue baking until top is crisp and golden brown, 25 to 30 minutes more. Let cool at least 10 minutes or, loosely covered, up to 30 minutes. Top with celery leaves; serve.