Pat the beef chuck roast dry with paper towels and season all sides with salt and black pepper.
Heat the olive oil in a large skillet over medium-high heat until shimmering.
Sear the roast in the hot oil for 3-4 minutes on each side until browned evenly. Remove from heat.
Place the sliced onion, carrots, and celery into the bottom of the slow cooker.
Add the minced garlic, dried thyme, dried rosemary, and bay leaves on top of the vegetables.
In a small bowl, whisk together the beef broth, tomato paste, and Worcestershire sauce until combined.
Place the seared roast on top of the vegetables in the slow cooker.
Pour the broth mixture over the roast and vegetables.
Cover the slow cooker with the lid and cook on low for 8 hours until the beef is tender and easily shredded.
Remove the bay leaves before serving.
Slice the roast against the grain and serve with the cooked vegetables and pan juices.