Preheat the oven to 180C/Gas 4.
Fry a chopped onion in some oil take out of frying pan
Fry your meat or sausages, so the outside is brown (braising steak is good chopped into 2cm cubes).
Add the onion back in (and garlic if you want) and a heaped tablespoon of plain flour - mix it round. Add 300 ml of the beef stock. Add in any combination of chopped carrot, potato, sweet potato, swede or parsnip. Give it a little stir.
Add a tablespoon of tomato puree and one teaspoon of mixed dried herbs
Put in enough hot stock to make sure everything's just covered and put it in the oven. After 15 minutes, put the lid on the casserole.
Cook beef casserole for at least one hour (or 45 minutes for the sausage casserole) - longer makes the meat more tender, but don't let it dry out and burn, so add more stock if needed.