In the 8-quart pot, heat the canola oil over medium-high heat. Add the beef soup bones and the meat. Cook until brown on all sides, about 5 minutes. Add the garlic and cook for another minute.
Add the beef stock, wine, Guinness, tomato paste, sugar, Worcestershire sauce, thyme, and bay leaves, then stir. Bring to a boil, then reduce heat to medium-low. Cook covered at a simmer for about 1 hour.
While the soup simmers, melt the butter in the 6-quart pot. Add the prepared potatoes, onion, and carrots. Saute until the vegetables are golden, about 20 minutes. Turn off the heat and set aside until the soup has simmered for 1 hour.
Remove the bones from the stew. Add the potatoes, carrots, and onions. Simmer uncovered until the vegetables and beef are tender, about 40 minutes. Remove the bay leaves and thyme stems, then skim the fat off the surface. Season to taste with kosher salt and fresh ground pepper.
Ladle soup into bowls, sprinkle fresh parsley on top, then serve.