In a small bowl, mix together the custard powder and 1/2 cup of the milk; set aside.
Sprinkle the sugar into a saucepan over medium heat. When the sugar begins to caramelise, add the remaining milk and coffee to the pan; bring to the boil. Reduce heat to low; cook, stirring until the sugar dissolves. Stir in the custard powder mixture; cook, stirring until the custard thickens. Remove from heat; whisk in the egg yolk.
Whip the egg white until soft peaks form. Fold the egg white into the custard mixture. Transfer to a serving dish or individual ramekins; refrigerate until firm.
This was a little too sweet however had a lovely flavour and was thick & creamy. Next time I would reduce the sugar to a quarter cup as caramelizing the sugar intensifies the flavour. The sugar really did get stiff when the milk mixture was added but melted down again as the recipe stated. Would like to try this with chocolate as a flavouring rather than coffee. - 29 Sep 2008