Trim the beef of visible fat and cut into 2.5cm (1 inch) cubes. Toss the beef in 30g flour to coat evenly.
Heat the oil in a large pot over medium-high heat. Shake off the excess flour from half the beef and add it to the pot. Brown on each side. Remove from the pot and set aside. Repeat with the rest of the meat.
Add the garlic, onion, celery and carrots to the pot and sauté for 2 to 3 minutes. Add the remaining flour and cook, stirring continuously, for 2 minutes.
Pour in 1/3 of the beef stock and cook for 2 to 3 minutes until the mixture thickens, scraping up the browned bits at the bottom of the pot. Stir in the tomato purée and rosemary.
Return the beef to the pot and add the potatoes and the rest of the stock. Add enough water to cover the meat and vegetables.
Bring to the boil, then turn down to the lowest heat. Cover with a lid and allow to simmer for at least 2 hours. The longer it cooks, the richer the flavour and the more tender the meat.
Check the thickness of the sauce is to your liking. If you prefer a thicker sauce, turn the heat up slightly and allow to boil uncovered until desired thickness. For a thinner sauce, add a little more water and stir through.
Just before serving, add the peas and heat through for about 5 minutes. Taste, and season with salt and pepper if needed. Serve piping hot.