01 - Pat the chuck roast dry and season all sides evenly with kosher salt and black pepper.
02 - Heat olive oil in a large skillet over medium-high heat. Sear the roast on all sides until browned, approximately 3 to 4 minutes per side. Transfer the roast to the slow cooker.
03 - Arrange carrots, potatoes, and sliced onion around and underneath the roast inside the slow cooker.
04 - Sprinkle minced garlic, dried thyme, dried rosemary, and bay leaves evenly over the roast and vegetables.
05 - In a bowl, whisk together beef broth, tomato paste, and Worcestershire sauce. Pour the mixture over the meat and vegetables in the slow cooker.
06 - Cover and cook on low heat for 8 hours, or until beef is fork-tender and vegetables are fully cooked.
07 - Remove the roast and vegetables to a serving dish. Discard bay leaves.
08 - Skim excess fat from the cooking liquid. In a small bowl, mix cornstarch and cold water to form a slurry. Stir the slurry into the hot liquid, cover, and cook on high for 5 to 10 minutes until the gravy thickens.
09 - Slice or shred the beef. Serve alongside the vegetables and spoon the gravy on top.