Heat olive oil in large pot over medium-high heat. Lightly salt the beef pieces. Add the beef to the pan and cook, without stirring, until nicely browned on one side, then use tongs to turn the pieces over. Continue to cook in this manner until all sides are browned, about 5 minutes. Add garlic and saute 1 minute. Add beef stock, Guinness, red wine, tomato paste, sugar, thyme, Worcestershire sauce, and bay leaves. Stir to combine. Bring mixture to boil. Reduce heat to medium-low, then cover and simmer 1 hour, stirring occasionally.
While the meat and stock is simmering, melt butter in another large pot over medium heat. Add potatoes, onion, and carrots. Saute vegetables until golden, about 20 minutes. Set aside until the beef stew in step one has simmered for one hour.
Add vegetables to beef stew. Simmer uncovered until vegetables and beef are very tender, about 40 minus. Discard bay leaves. Tilt pan and spoon off fat. Add salt and pepper to taste. Sprinkle with parsley and serve.
