Season the beef chuck roast generously with salt and pepper on all sides.

In a large skillet, heat olive oil over medium-high heat. Sear the roast for 3-4 minutes on each side until browned.

Transfer the seared roast to the slow cooker. In the same skillet, add the chopped onion and minced garlic. Sauté for 2-3 minutes until softened, then transfer to the slow cooker.

Arrange the carrots and potatoes around the roast in the slow cooker.

In a bowl, combine the beef broth, Worcestershire sauce, tomato paste, thyme, and rosemary. Mix well.

Pour the broth mixture over the meat and vegetables in the slow cooker.

Cover and cook on low for 8 hours or on high for 4 hours, until the meat is tender and easily shreds with a fork.

About 30 minutes before serving, taste the broth and adjust seasoning with salt and pepper if necessary.

Once cooked, carefully remove the roast and vegetables. Shred the meat with two forks and serve with the vegetables and broth.