Yield: 8 to 12 servings.
½ cup butter, plus more for the dish
2 medium onions, peeled and chopped
2 celery stalks, thinly sliced
1 sweet apple, cored and cut into ½-inch dice
1 tart apple, cored and cut into ½-inch dice
2 tablespoons fresh thyme leaves
1 tablespoon chopped fresh sage
3 tablespoons finely chopped flat-leaf parsley
1 cup roasted or steamed chestnuts, crumbled
8 cups unsweetened, slightly stale cornbread, cut into 1-inch cubes (see note)
1 teaspoon kosher salt, or to taste
½ teaspoon ground black pepper, or to taste
2 large eggs
1½ to 2 cups richly flavored turkey or chicken broth
Preheat oven to 350°. Generously butter or mist with cooking spray a 9 x 13-inch baking dish or iron skillet.
Melt butter in a large skillet over medium-high heat. Add onions, celery, and a pinch of salt. Cook, stirring often, until mixture begins to soften, about 10 minutes.
Stir in apples and cook, stirring often, until tender, about 3 minutes.
Stir in thyme, sage, parsley, and chestnuts and cook for 2 minutes, stirring often. Pour into a large bowl.
Stir in cornbread. Season with salt and pepper.
In a small bowl, whisk eggs until the whites and yolks are blended, and then stir into the bread mixture.
Stir in enough broth to make the dressing quite moist, but not so much that there is standing liquid in the bottom of the bowl. Pour into the prepared baking dish or skillet.
Cover with aluminum foil and bake for 20 minutes. Remove foil and bake until the dressing is set and lightly browned on top, about 25 minutes longer. Let stand for 10 minutes before serving warm.
Note: If your cornbread is freshly made, spread the cubes in an even layer on a baking sheet and let stand, uncovered, overnight, or pop it into a 300° oven for 10 minutes. The cubes should be firm enough to hold their shape when gently squeezed, but not as dry as croutons.