1 1/2 French baguettes, cut into 1-2 inch cubes (about 10–12 cups)
8 T unsalted butter, divided
4 celery stalks, diced or thinly sliced
1 shallot, minced
1 large yellow onion, diced
5 cloves garlic, minced
2 T chopped fresh sage
1 T chopped fresh thyme
3 c low-sodium chicken or vegetable broth
1 tsp salt, more or less to taste
Crisp the Bread: Preheat oven to 450 degrees and place cubed bread onto a large rimmed baking sheet. Bake for 12-13 minutes, tossing halfway, until golden and crispy. Remove from oven and let cool completely.
Cook the onion, shallots, celery, herbs, and garlic: Melt 3 T butter in a large oven safe skillet over medium high heat. Add onion, shallots, and celery and cook until tender, about 7-8 minutes. Add garlic, sage, and thyme, and cook another minute or so, until garlic and herbs are really fragrant.
Mix Bread with broth and eggs: Whisk eggs and broth together in a large bowl. Add in crispy bread and toss until evenly coated. Stir occasionally to saturate all pieces of bread.
Add onion mixture to bread mixture: Stir onion mixture into bread mixture and toss to combine.
Transfer stuffing back to skillet: Melt 3 T butter in the now empty skillet over low heat. Add stuffing back to skillet, and using a wooden spoon press down into even layer. Let cook for 5-7 minutes, until bottom is golden. Melt remaining 2 T butter and brush over the top of the stuffing.
Bake! Reduce oven to 425 degrees and bake for 17-20 minutes, until top is golden brown. Let cool for 10 minutes before serving.