01 - Toss beef cubes with flour, 1 tsp salt, and ½ tsp pepper in a large bowl until evenly coated.
02 - Heat 2 tbsp oil in a large Dutch oven over medium-high heat. Brown beef in batches, adding more oil as needed. Transfer browned beef to a plate.
03 - Add remaining oil to the pot. Sauté onion and garlic for 2-3 minutes until fragrant and translucent.
04 - Stir in tomato paste and cook for 1 minute to deepen flavor.
05 - Add carrots, potatoes, parsnips, and celery. Stir to combine with aromatics.
06 - Return beef to pot. Pour in beef broth and Guinness. Add Worcestershire sauce, bay leaves, thyme, rosemary, and sugar.
07 - Bring to boil, then reduce heat to low. Cover and simmer for 1.5-2 hours, stirring occasionally, until beef is fork-tender and vegetables are cooked through.
08 - Discard bay leaves. Adjust seasoning with salt and pepper as needed.
09 - Ladle stew into bowls and garnish with chopped parsley. Serve hot with crusty bread.