Combine salt, paprika, pepper, thyme, and oregano in a small bowl and set aside. In a separate bowl, pour 1 cup of hot water over the dried porcini mushrooms and let them soak for 20 minutes to rehydrate and release their umami flavor. After soaking, carefully drain the mushrooms through a fine strainer, reserving the liquid (this mushroom broth is liquid gold for the sauce). Finely chop the rehydrated mushrooms and set both the chopped mushrooms and reserved liquid aside.

Pat the brisket completely dry with paper towels—this is essential for proper browning and crust development. Generously rub the entire surface of the meat with the spice mixture from Step 1, working it into the meat on all sides. Let the seasoned brisket sit at room temperature for 15-20 minutes while you prepare the oven and other ingredients. I like to do this while preheating, as it allows the seasonings to penetrate slightly and the meat to cook more evenly.

Preheat your oven to 350°F. Heat 3.5 tablespoons of olive oil in a large Dutch oven or heavy roasting pan over medium-high heat until shimmering. Once the oil is hot, carefully place the brisket in the pan and sear for 6 minutes on the first side without moving it—this develops a deep, flavorful crust. Flip the brisket and sear the other side for 4 minutes. Remove the brisket to a plate and set aside. Pour the vermouth, chicken stock, and reserved mushroom liquid into the pan, scraping up all the flavorful browned bits from the bottom with a wooden spoon for 2 minutes—this deglazing step captures all the caramelized flavor into your sauce.

Stir the tomatoes, chopped mushrooms from Step 1, and bay leaves into the braising liquid. Place the seared brisket back into the pan, nestling it into the sauce. Top the brisket with the sliced onions and minced garlic, spreading them evenly across the surface—this creates a protective barrier that keeps the meat moist during the long braise. I find that layering the onions on top, rather than just mixing them in, helps them caramelize beautifully and creates a wonderful textured topping.

Bring the braising liquid to a boil on the stovetop, then immediately transfer the uncovered Dutch oven to the preheated 350°F oven and roast for 30 minutes. Remove from the oven and cover tightly with foil, then return to the oven and braise for 2 to 2.5 hours until the brisket reaches an internal temperature of 200°F when tested with a meat thermometer. The meat should be completely tender and pull apart easily when done. Check the temperature after 2 hours so you don't overcook it—you're aiming for that sweet spot where it's fall-apart tender but not stringy.

Remove the brisket from the pan and transfer it to a cutting board. Let it rest for 10 minutes—this allows the juices to redistribute, keeping the meat moist when sliced. While the brisket rests, use a slotted spoon to remove the bay leaves from the braising liquid and discard them. Simmer the sauce on the stovetop over medium heat for 10-15 minutes to reduce it slightly and concentrate the flavors. Slice the brisket against the grain into 1/4-inch thick slices, which ensures maximum tenderness.

Arrange the sliced brisket on a serving platter and top with the caramelized onions from the pan. Pour the reduced sauce over everything, making sure to include plenty of the mushrooms and braising liquid. This dish is perfect for a Thanksgiving table, as it can be prepared a day ahead and reheated gently before serving.