Using a non-stick pan, sweat the onion until transparent and just beginning to caramelize, but do not burn. Add the stock, and cook until the onion is soft.
Meanwhile, pre-heat the oven to 200 °C / 400 °F / Mark 6, bring the milk to the boil and, in another saucepan melt the butter. Stir the flour into the butter, and cook for 5 minutes. Slowly add
Divide the mixture between six ovenproof soup bowls placed on a baking sheet. Beat the egg yolks into the roux that you have set aside, whisk the whites to firm peaks, and gently fold the two together. Spoon this soufflé mixture on top of the soup bowls, and bake in the preheated oven for 10–12 minutes. Serve at once.
© 1995 Frances Bissell. All rights reserved.