Set oven to preheat at 300°F.
Season the chuck roast liberally with Kosher salt and black pepper on all surfaces.
In a 7 to 8 quart Dutch oven over medium-high heat, warm 2 tablespoons of olive oil. Sear the meat undisturbed on each side for 5 to 6 minutes until a golden crust forms. Remove the roast and set aside, keeping the flavorful bits in the pot.
Lower the heat to medium. Add sliced onions and sauté for about 3 minutes until they begin to brown, stirring and scraping the pot to release browned bits. If necessary, add a splash of broth to aid deglazing. Stir in the minced garlic and cook for another minute.
Pour in the red wine (or beef broth) and deglaze the pot thoroughly. Add 2 cups of beef broth, tomato paste, Worcestershire sauce, thyme, rosemary, and bay leaves. Mix well and bring the mixture to a low boil.
Return the roast to the pot, along with any accumulated juices. Ensure the liquid rises to halfway up the meat; supplement with more broth if needed. Cover tightly with the lid and place in the oven. Bake for 1 hour and 30 minutes.
Remove from the oven, then nestle in the baby carrots and potatoes. Adjust seasoning with salt and pepper if desired. Re-cover and continue baking for an additional 2 hours, or until the meat is fork-tender and vegetables are cooked through. Extend by 15–30 minutes for extra tenderness if preferred.
Garnish with chopped parsley if using, and serve directly from the Dutch oven or transfer to a serving platter.