Herby Stuffing with Sourdough Bread

Preheat oven to 350 degrees. Grease a 9 by 13-inch baking dish.
Spread bread cubes in a single layer on a baking sheet (use a second one if needed). Bake until bread cubes are dry and beginning to brown - about 20 minutes. Transfer to a large bowl.
In a large skillet over medium heat, melt 2 tablespoons of butter. Add the mushrooms and sprinkle with salt. Cook, stirring occasionally, for 6-8 minutes, until golden brown. Add the celery, onion, thyme leaves, and 2 more tablespoons of butter. Cook about 5 more minutes, until the vegetables have softened. Add the sage and the remaining 4 tablespoons of butter and cook until the butter has melted. Stir in the chicken broth. Season generously with salt and pepper to taste - remember the seasonings will be slightly diluted by the bread.
Pour the chicken broth mixture over the bread cubes in the mixing bowl. Toss to combine and let sit for a couple minutes to soak up the liquid. Use a slotted spoon to transfer the bread cubes to the prepared baking dish, packing the bread cubes in so they're dense. If any liquid remains in the bowl, you can add it to your liking, or reserve it for soups or gravy. Top with parsley.
Bake on the center rack for 40 minutes, until heated through and top is golden brown. Allow to sit for 15 minutes before serving.