Fold in 8 stiffly beaten egg whites mixing them in gently with a spoon.
Mould nearly all this mixture in a high oval shape in a buttered and sugared oval dish. Smooth with a palette knife then decorate it with the remainder of the mixture using a piping bag and star tube. Cook in a moderate oven for the amount of time as determined by the size of the omelette. Remove from the oven 2 minutes before it is ready, and dredge with icing sugar. Replace in the oven so that the sugar will melt and cover the omelette with a caramelized coating.