4 cups thinly sliced Spanish onions
3 cups peeled, coarsely chopped carrots
3 cups chopped celery
2 cups grain mustard
2 envelopes Lipton onion soup mix
1 brisket, preferably "first cut," 5 to 6 pounds, with a good amount of marbling
1/3 cup Worcestershire sauce
1/3 cup red or white wine (whatever is open)
1/3 cup canola oil 1/4 cup minced flat-leaf parsley leaves
5 cloves garlic, minced
2 bay leaves
Kosher salt and freshly ground black pepper
Preheat the oven to 400 degrees Fahrenheit.
Line the bottom and sides of a roasting pan with aluminum foil.
Put the onion, carrots, celery, garlic and bay leaves in a large mixing bowl and toss.
Spread the mustard all over the brisket. Sprinkle 1 envelope of soup mix on each side of the brisket. Put half of the vegetables in the pan. Place the brisket, fat-side up, on top of the vegetables, then top the meat with the remaining vegetables. Pour the wine, Worcestershire and oil over the meat and vegetables.
Cover the pan tightly with aluminum foil, and cook for 2 hours.
Lower the temperature of the oven to 350°F and cook for 4 hours.
Remove the pan from the oven and uncover. Lower the heat to 320°F. Cook, uncovered, until the meat is tender, about 45 minutes, being careful not to let it dry out.
Baste the brisket several times in its own juice.
Remove the pan from the oven, and let the brisket cool to room temperature.
Slice the meat against the grain, as thinly as possible. Put the sliced meat back into the sauce and vegetables.
To serve, sprinkle with the parsley and cover the pan with aluminum foil. Heat the brisket in a 325 degrees Fahrenheit oven until hot.