- Preheat the oven to 375°F.
- Coat a large wide, shallow pan with olive oil and bring it to high heat.
- Season the brisket generously with salt and add it to the pan. Brown the meat well on all sides, about 20 minutes total. Don’t skimp on this step—BROWN FOOD tastes good. Remove the brisket from the pan and reserve. Ditch the oil.
- Add a few drops of fresh oil to the pan and toss in the bacon. Bring the pan to medium heat and cook until the bacon is brown and crispy, 6 to 7 minutes.
- Toss in the onions, celery, and garlic and season with salt. Cook until the veggies are tender, 7 to 8 minutes.
- Add the mushrooms and cook for 2 to 3 more minutes.
- Add the balsamic vinegar and cook until evaporated by half, 5 to 6 minutes. Taste it—at this point it will be very vinegary—that’s okay. Season with salt if needed. BTW: Salt offsets acid so it will help take down the vinegar flavor a little bit.
- Transfer the mixture to a roasting pan and lay the brisket on top. Add the chicken stock and jiggle the pan to nestle everyone together comfortably. Toss in the thyme bundle and bay leaves. Cover the pan with foil and place in the oven. Braise the brisket for 1 hour, then turn and braise for 1 more hour. Remove the foil and cook for 30 minutes more.
- Remove the brisket from the oven, transfer to a cutting board, cover loosely with foil, and let rest for 20 minutes.
- Skim any excess fat from the cooking liquid, taste, and reseason if needed.
- Slice the brisket against the grain on the bias. Serve drizzled with the sauce and sprinkled with chives.
Get a free printable with holiday recipes from our favorite celebrated chefs.