Heat the oven to 325°F. Pat the chuck roast very dry, season it generously with kosher salt and freshly ground black pepper, and lightly dredge it in the optional flour if you prefer a thicker, more gravy-like sauce.

Heat the olive oil in a large Dutch oven over medium-high heat. Brown the roast thoroughly on every side, about 4-5 minutes per side, then transfer it to a plate.

Add the onions, carrots, celery, and garlic to the Dutch oven. Cook for 8-10 minutes, stirring occasionally, until the vegetables begin to soften and develop golden-brown edges.

Pour in the red wine and Cognac or brandy. Scrape the browned bits from the bottom of the pot and simmer for several minutes so the liquid becomes fragrant and slightly reduced.

Add the crushed tomatoes and their juice, stock, optional bouillon cube, thyme bundle, and bay leaves. Return the roast and any accumulated juices to the pot, keeping the liquid roughly one-third to halfway up the meat.

Cover the Dutch oven tightly and braise in the oven for approximately 3-3 1/2 hours, turning the roast once or twice. Continue cooking until it is genuinely fork-tender; a shreddably tender roast will generally reach at least 190°F internally, although tenderness matters more than a particular final temperature.

Transfer the roast to a cutting board and rest it for 15-20 minutes. Remove the thyme bundle and bay leaves, skim excess fat from the sauce, adjust the seasoning, then slice or pull apart the beef and serve it with the vegetables and sauce.