By the way, I didn't find the authentic Irish Stew Recipe.
The Irish stew that I have seen (in the North of Ireland) has only 4 ingredients + water, potatoes, onions, carrots and meat (stewing steak or lamb). I dare say some people may now add extra ingredients like swede but I have always seen it with the former.
This is simmered for about 40 minutes until most of the water has evaporated and the stew is so thick that you could serve it on a plate rather than a bowl. :)
Like the Polish bigos it gets better when you reheat it next day.