This crowd-pleasing brisket is juicy, tangy and slightly sweet. It's perfect for special occasions and holidays. Our low-and-slow cooking method and flavorful braising liquid make this tough cut incredibly tender. Be sure to ask your butcher for a first-cut brisket, which is meatier than the fatty second cut.
Preheat the oven to 275 degrees F. Mix the fennel seeds, sage, cayenne, 1 tablespoon salt and 1/2 teaspoon black pepper in a small bowl. Rub the spice mixture all over the brisket, pressing it into the meat to make sure it sticks well.
Mix the beef stock or broth, balsamic vinegar, brown sugar and garlic in a large liquid measuring cup and set aside.
Heat the olive oil in a Dutch oven or large heavy-bottomed pot with a lid over medium-high heat. Add the brisket fat-side up and cook until golden brown and no longer sticking to the bottom of the pot, 4 to 5 minutes. Flip and cook the other side until it is golden brown and some of the fat has rendered, 2 to 3 minutes. Remove the brisket to a plate and lower the heat to medium.
Add the onions, carrots and 1 teaspoon salt and cook, stirring occasionally and scraping up any browned bits from the bottom of the pot, until the onions are softened and starting to caramelize, 7 to 8 minutes.
Add the balsamic mixture and tomatoes to the pot and bring to a boil. Return the brisket to the pan and nestle it into the sauce and vegetables fat-side up. Cover the pot, transfer to the oven and braise until the brisket is tender but not shredding or falling apart, about 3 hours 30 minutes. A fork should easily pierce through the meat.
Remove from the oven, uncover and let the brisket rest in the pan for 30 minutes. Remove the brisket to a cutting board. Bring the vegetables and sauce to a boil over medium-high heat and cook until slightly thickened, 12 to 15 minutes. Thinly slice the brisket across the grain and place on a platter. Spoon the vegetables and sauce over the top and serve.
Whole beef briskets are sold as two separate cuts. The first cut, also known as the flat cut, is leaner and slices more neatly. The second cut, also called the deckle, is fattier. We used a first-cut brisket in this recipe.