This is a wonderfully old-fashioned and comforting dish, from one of my favourite cookbooks, Plats du Jour by Patience Gray and Pimrose Boyd (published 1957). I can’t recommend this book too highly; it’s so old-fashioned that words like pizza and courgettes are printed in italics, and the recipes owe absolutely nothing to fashion and everything to love of good, simple food.
Anyway, you would normally use a boiling chicken for this, difficult to find nowadays, so just use a nice free-range chicken and reduce the poaching time.