Heat the vegetable oil in a large Dutch oven or stockpot over medium heat. Season the chuck roast with salt and pepper, then sear it on all sides until browned. Remove the beef and set it aside on a plate.
In the same pot, add the carrots, celery, and onion. Sauté for 4-5 minutes until the vegetables begin to soften. Add the minced garlic, dried parsley, oregano, and thyme, cooking for another minute while stirring constantly.
Pour in the beef broth and diced tomatoes, then add the bay leaf and the seared beef back to the pot. Bring to a boil, reduce heat, and simmer for about 1.5 hours, or until the beef is tender.
Add the barley and drained corn to the pot. Cover with a lid and simmer for an additional 30 minutes. Remove the lid and simmer for another 15 minutes to ensure the barley is fully cooked.
Remove the beef from the pot, trim any fat or gristle, and shred or cut the beef into bite-sized pieces. Return the beef to the pot, stir well, and adjust seasoning as needed. Discard the bay leaf before serving.