Cornbread dressing (Southern-style)

Steps

1. Cornbread, preferably the day before: preheat the oven to 220 °C (425 °F) with a 25 cm (10 in) cast iron skillet inside. Whisk together the cornmeal, flour, baking powder, baking soda, and half of the salt. Whisk the buttermilk with two of the eggs.
2. Carefully remove the hot skillet, melt half of the butter in it while swirling to coat, then pour this melted butter into the buttermilk mixture. Quickly stir the wet and dry ingredients together just until no dry flour remains, and pour the batter into the hot skillet: it should sizzle.
3. Bake for 20 to 25 minutes, until the top is golden and a toothpick inserted in the center comes out clean. Let cool, crumble coarsely into a large mixing bowl, and let dry uncovered for a few hours or overnight.
4. The day of serving, preheat the oven to 175 °C (350 °F) and butter a 23 x 33 cm (9 x 13 in) baking dish. Cut the sandwich bread into small cubes and add it to the crumbled cornbread.
5. Finely chop the onions and dice the celery. Melt the remaining butter in a skillet over medium heat and sweat them for 10 minutes, until tender and translucent. Add the rubbed sage and dried thyme, crumbling them between your fingers, along with the pepper and the remaining salt, and stir for 1 minute.
6. Pour the vegetables over the cornbread, followed by the warm broth, and mix: the mixture should have the consistency of a thick, wet batter, much wetter than a bread stuffing, otherwise the dressing will turn out dry. Taste and adjust the salt, then fold in the remaining two beaten eggs.
7. Spread into the baking dish without packing it down. Bake uncovered for 45 to 50 minutes at 175 °C (350 °F), until the edges and top are browned, the center is set, and it registers 165 °F (74 °C) on an instant-read thermometer. Let rest for 10 minutes before serving.