As soon as the potatoes are cool enough to handle, slice them roughly. Heat the dripping or oil and add the potatoes. Cook them until they are well browned and at the last moment add the sausage and heat through. Season well.
Remove from the pan and keep warm. Add a little more dripping or oil and over a brisk heat cook the cabbage for a few minutes. It needs to retain its crispness. Remove from the heat and spoon onto the potatoes. Return the pan to the heat, add the vinegar to deglaze and then the stock. Allow to cook fiercely for half a minute and then pour over the potatoes and the cabbage. Eat at once.