Pat the chuck roast dry and season all sides with salt, pepper, garlic powder, onion powder, thyme, and rosemary.
Heat olive oil in a skillet over medium-high heat and sear the roast for 3–4 minutes per side.
Add the onion, carrots, potatoes, and garlic to the bottom of the crockpot.
Place the seared roast on top of the vegetables.
Add the beef broth, Worcestershire sauce, tomato paste, and bay leaves.
Cover and cook on LOW for 8–9 hours or HIGH for 4–5 hours, until the beef is fork-tender.
Transfer the roast and vegetables to a serving platter.
Remove the bay leaves.
Mix cornstarch and cold water until smooth. Stir into the cooking liquid and simmer until thickened.
Slice or shred the roast and serve with the vegetables and gravy.