Loved these while travelling in Ireland recently - however these turned out better than most of the ones we were served there. It seems that most of the B&Bs bought their potato bread from the supermarket - they're so easy to make and so good when you do I can't imagine why!
I'm in NZ and my mashed potato also had a bit of purple kumara in it - you'd never pick it if you didn't know but I think the little bit of sweetness it added was perfect. Apart from that, I followed this recipe exactly. The ½ pound of potato converts to 225g (of course). I'm at our holiday home and don't have scales so am using cup measures for the batch I'm about to make - will use a ratio of about 1 cup potato to ½ cup flour.