In a large non stick pan, brown the steak in batches and place in crock pot or casserole dish. Then add the carrots, celery, mushrooms and onion.
Combine the tomatoes, water, stock cubes, wine, herbs, salt and pepper.
Pour into the crock pot and cook on low for 8 hours or high for 5 hours approximately If you are not using a crock pot, cover the casserole and place in a moderate oven for 1 1/2-2 hours or until beef is tender.
Sieve the flour into a bowl; add suet, parsley, salt and pepper. Add about 3 tbsp water to make a soft but not sticky dough. With floured hands roll dough into 8 balls.
Add the dumplings 30-40 minutes before the end of cooking time and cook on a high setting.
On completion of cooking, thicken the sauce with gravy granules if desired (or needed) for a rich beefy flavour.