How to Make It
Put the pork in a large bowl. Add the wine, onion, carrot, bouquet garni, spice bundle and olive oil. Cover and refrigerate overnight.
The next day, pour the pork into a colander set over a bowl. Discard the onion and carrot. Squeeze the spice bundle over the meat, then discard the bundle. Reserve the pork, bouquet garni and the marinade.
In a bowl, soak the porcini in 1 cup of hot water until softened, about 20 minutes. In a large skillet, heat 2 tablespoons of the oil. Season the pork with salt and pepper. Add half of the pork to the skillet and cook over moderately high heat until well-browned all over; transfer to a plate. Repeat with the remaining pork.
Return all of the pork to the skillet and sprinkle with the flour. Stir over moderate heat until the flour has dissolved, about 1 minute. Add the brandy and carefully ignite it with a long match; shake the skillet until the flames die down. Return the pork to the plate. Add the remaining 1 tablespoon of olive oil to the skillet along with the onion and carrot. Season with salt and cook over moderately low heat, stirring occasionally, until the vegetables are lightly browned, about 10 minutes.
Lift the porcini from the soaking liquid and coarsely chop them; reserve the soaking liquid. Add the porcini to the skillet and cook for 3 minutes, stirring.
Preheat the oven to 250°. Line the bottom of a 4 1/2-quart enameled cast-iron casserole with the pork skin, fat side down. Spoon 1/3 of the pork over the skin followed by 1/3 of the vegetable mixture and 1/3 of the garlic cloves. Season with salt and pepper and sprinkle with some of the juniper berries. Repeat this layering 2 more times.
Return the skillet to moderately high heat. Pour in the reserved porcini soaking liquid, stopping before you reach the grit at the bottom. Add the reserved pork marinade and bring to a simmer, scraping up any browned bits from the bottom of the skillet. Boil until reduced to 2 cups. Pour this liquid over the daube.
Tuck the reserved bouquet garni into the daube. Add enough water to the casserole to just cover the meat and bring to a boil over moderately high heat. Place a round of parchment paper directly on the surface of the meat and cover with the lid. Transfer the casserole to the oven and bake until the meat is tender, about 2 1/2 hours. Let cool to room temperature. Discard the parchment paper, bouquet garni and any bits of juniper berry. Refrigerate the daube overnight.
Preheat the oven to 250°. In a large skillet, heat 2 tablespoons of the oil until shimmering. Add the oyster and cremini mushrooms and season with salt and pepper. Cover and cook over moderate heat, stirring occasionally, until the mushrooms are softened, about 5 minutes. Remove the lid. Continue cooking, stirring occasionally, until the liquid has evaporated and the mushrooms start to brown, about 4 minutes. Add the remaining 1 tablespoon of olive oil and the garlic and cook, stirring, until fragrant, about 3 minutes. Stir in the chopped parsley.
Scrape the fat from the surface of the daube and discard it. Mix the mushrooms into the daube and bring to a simmer over high heat, stirring frequently. Bake the daube for about 1 1/2 hours, uncovered, until the liquid has reduced slightly and the meat is very tender. Stir in the vinegar, season with salt and pepper and serve.