Prepare the Beef: Trim any large, easily removable pieces of fat from the beef chuck roast. Thoroughly pat the meat dry with paper towels. In a small bowl, mix together the dried oregano, ground cumin, paprika, ground black pepper, and kosher salt. Evenly sprinkle this spice blend over all sides of the beef, gently rubbing it into the meat.
Sear for Flavor: Heat the olive oil in a large nonstick skillet over medium-high heat until shimmering. Carefully add the seasoned beef to the hot skillet. Brown the roast well on all sides, typically 2-3 minutes per side, to develop a rich flavor base.
Build the Slow Cooker Base: While the beef sears, add the chopped onion, minced garlic, and carrot chunks to the insert of your 4- to 6-quart slow cooker. Tuck in the bay leaf. Pour the beef broth over the vegetables.
Combine and Cook: Once browned, carefully transfer the seared beef roast from the skillet and place it atop the vegetables within the slow cooker. Secure the lid onto the cooker.
Choose Your Cooking Path: Cook the roast on the LOW heat setting for 8 to 10 hours, or alternatively, cook on the HIGH heat setting for 4.5 to 5.5 hours. The goal is exceptionally tender beef.
Add the Cabbage: Approximately 30 minutes prior to the total cooking time being complete, if you were cooking on LOW, switch the setting to HIGH. Carefully remove the lid and distribute the shredded cabbage over the beef and carrots. Resecure the lid.
Finish Cooking: Continue cooking on the HIGH setting for the final 30 minutes, allowing the cabbage to wilt and become tender.
Serve: Gently transfer the tender beef roast to a cutting board; it can be sliced or easily shredded with forks. Remove and discard the bay leaf from the slow cooker contents. Using a slotted spoon, serve the cooked carrots, onion, and cabbage alongside portions of the beef. Ladle some of the flavorful cooking juices over each serving, if desired.