Preheat your oven to 300°F.
Season the beef chuck roast with salt and black pepper on all sides.
In a large Dutch oven, heat the olive oil over medium-high heat. Add the beef roast and sear it for about 4-5 minutes on each side until browned. Remove the roast and set it aside.
In the same pot, add the chopped onion and sauté for about 3-4 minutes until softened. Stir in the minced garlic and cook for an additional 1 minute until fragrant.
Pour in the beef broth and balsamic vinegar, scraping up any browned bits from the bottom of the pot.
Add the cranberry sauce, brown sugar, thyme, rosemary, and bay leaf. Stir to combine.
Return the beef roast to the pot, ensuring it is submerged in the liquid. Cover the pot with a lid and transfer it to the preheated oven.
Braise the beef for 3-4 hours, or until it is fork-tender. Check occasionally and add more broth if needed to keep the liquid level up.
Once done, remove the pot from the oven and let it rest for 10-15 minutes before slicing. Serve with the sauce spooned over the top.