Warm the oil in a heavy bottomed frying pan and cook the sausages until just done. Transfer to casserole reserving the fat from the sausages in the frying pan.
Add a little more oil if necessary. Fry the onion, garlic, celery & carrots for a few minutes until soft. Add the flour and stir to mix. Heat the mixture through for a little while and transfer to casserole.
Combine all the other dry ingredients and pour over the boiling water. Add the wine, tomatoes and beans. Pour sauce into the casserole and stir all the ingredients together.
Place casserole in the oven and bake and about an hour a moderately slow oven.