Cut your loaf into half-inch cubes and leave them out on the counter overnight, uncovered, so they turn stale and sturdy. If you're short on time, spread them on a baking sheet and bake at 300°F for about 30 minutes until they feel crisp and dry. Dry bread is non-negotiable here, since fresh bread turns to mush once it absorbs the broth.
Melt the butter in a large skillet over medium-high heat until it starts to foam and smells nutty. Add the chopped onion and celery, stirring often, and cook for about 7 to 8 minutes until they turn soft and translucent. This step builds the savory base that flavors every single bite of the finished stuffing.
Once the vegetables are tender, stir in the parsley, sage, thyme, and marjoram directly into the skillet. Cook for about 30 seconds, just until the herbs become fragrant and the kitchen smells incredible. Pull the skillet off the heat right away so the herbs don't scorch or turn bitter.
In a large bowl, whisk the eggs until smooth, then pour in the chicken broth along with the salt and pepper. Whisk everything together until it's fully combined and slightly frothy. This mixture is what moistens the bread and holds the whole dish together once baked.
Pour the buttery vegetable and herb mixture into the bowl with the eggs and broth, stirring well to combine. Add the dried bread cubes and gently toss everything together until each piece is evenly coated. Work carefully here so you don't crush the bread cubes into crumbs.
Transfer the mixture into a buttered 9x13-inch baking dish, spreading it into an even layer. Cover tightly with foil and either refrigerate for up to 24 hours or freeze for longer storage. This is the exact point where you get to walk away and let your future self handle the baking.
When you're ready to serve, preheat your oven to 400°F and keep the dish covered with foil. Bake for about 25 minutes if refrigerated, or closer to 45 minutes if frozen, until mostly heated through. Remove the foil and bake for another 10 to 20 minutes until the top turns golden and crispy.