Preheat oven to 300°F (150°C). Season roast generously with salt and pepper.
Heat olive oil in a Dutch oven over medium-high heat. Sear roast on all sides until deeply browned. Remove and set aside.
Add onion to the pot and cook 3–4 minutes until softened. Stir in garlic for 30 seconds.
Pour in beef broth, scraping up browned bits. Stir in tomato paste, Worcestershire, thyme, and rosemary.
Return roast to the pot. Add carrots and potatoes around it.
Cover and transfer to oven. Cook for 3–3½ hours, until beef is fork-tender.
Optional: Remove roast and veggies. Simmer liquid on stovetop and whisk in cornstarch slurry to thicken.
Slice or shred beef, spoon gravy over top, and serve warm.