Season 2 ½ pounds beef brisket with 1 teaspoon kosher salt and 1 teaspoon ground black pepper. Heat a large skillet over medium-high heat and add 1 tablespoon of the 2 tablespoons olive oil. Sear the brisket on both sides until nicely browned, about 3-5 minutes per side. Remove to a plate.
Reduce the heat to medium, then add the remaining tablespoon of olive oil to the skillet, then add 1 cup diced onion, 1 cup diced carrots, and 1 cup celery. Cook for 2-3 minutes, then add 1 tablespoon minced garlic. Cook for 1 more minute, then add the vegetable mixture to the slow cooker.
Add 1 (5.5-ounce) can tomato paste, 1 (14-ounce) can diced tomatoes, 2 cups beef broth, ¾ cup dry red wine, and 1 teaspoon dried Italian seasoning to the slow cooker and stir to combine.
Add the brisket to the slow cooker. Cover and cook on LOW for 8 hours, or on HIGH for 4-5 hours, until easily shredded with two forks. Serve over pasta, mashed potatoes, or polenta.
Notes
Storage Recommendations
Fridge: Store in an airtight container for up to 7 days. Reheat in the microwave or on the stovetop until warmed through.
Freezer: Freeze in a freezer-safe container for up to 3 months. Thaw completely before reheating.
Make Ahead: Prepare 2–3 days in advance and refrigerate. Reheat on the stovetop for 10–15 minutes before serving.