01 - Preheat the oven to 325°F.
02 - Coat beef pieces evenly with flour, shaking off any excess.
03 - Heat vegetable oil in a large ovenproof casserole dish over medium-high heat. Brown beef in batches, then set aside.
04 - Add onions, garlic, carrots, and celery to the pan and sauté for 5 minutes until softened.
05 - Stir in tomato paste and cook for 1 minute. Deglaze with red wine if using, scraping up browned bits.
06 - Return browned beef to the dish. Add beef stock, bay leaves, thyme, rosemary, salt, and pepper. Bring to a simmer.
07 - Cover and transfer to the oven. Cook for 2 hours, stirring once or twice.
08 - In a bowl, blend flour, baking powder, and salt. Rub in cubed butter until mixture resembles breadcrumbs. Stir in milk and parsley to form a soft dough.
09 - Remove casserole from oven and increase the oven temperature to 400°F.
10 - Drop spoonfuls of dumpling dough over the casserole surface, forming about 12 dumplings.
11 - Return the dish uncovered to the oven and bake for 25 to 30 minutes until dumplings are puffed and golden and the stew is bubbling.
12 - Remove bay leaves and serve hot.