Two nights ago, in honour of my Irish forebears, I made Dublin Coddle for supper. When I mentioned this culinary achievement in an e-mail to a friend in Lincolnshire, he wrote back asking what such a thing could be. I was shocked, thinking that everyone in the British Isles knew of this classic Irish dish of potatoes, bacon, sausage, and onions simmered in broth. How wrong am I?