Preheat oven to 350 degrees. In a large heavy ovenproof pan (le crueset) or dutch oven, heat the oil over medium high heat. Pat the roast dry rub to coat with salt and pepper. Brown the meat on all sides in the heated casserole. Add in the onions and celery, stir and cook for 2 minutes or until softened. Stir in the garlic and cook for 30 seconds. Add the tomatoes, red wine, beef stock and bay leaf and bring to a simmer. Cover and place pot in oven to braise.
After 1 hour, remove pot and stir in carrots. Return to oven for another 30 minutes. Remove pot from oven and stir in potatoes. Return to oven for another 30 minutes or until the meat and vegetables are tender.
When the meat is tender, remove it to a platter. Remove vegetables to a bowl and cover to keep warm. Using a large spoon, skim off the excess fat from the remaining cooking juices. Bring liquid to a simmer on the stovetop. Slowly stir in half of the cornstarch mixture and simmer to thicken. Add more cornstarch mixture until desired gravy consistency is reached. Taste and season with salt and pepper. Stir in the parsley.
Slice the beef and place on platter surrounded with the vegetables. Serve with gravy.