Prepare all the ingredients.

Whisk the egg and sugar...

...for 5 minutes until pale and thick. Add the sifted flour and mix well.

Beat the egg whites until stiff (5 egg whites give exactly 1/4 liter. If needed, add or substract an egg, depending on their size)...

...and stiffen them halfway through with the remaining sugar.

Combine gently the meringue with the egg and sugar mix...

...using a wooden spatula or a maryse.

This batter can't wait, you have to use it immediately.

Fill up a pastry bag with a regular tip. You can use a scraper.

Arrange on a buttered and floured baking sheet or on buttered baking paper or on siliconed "fiberlux" paper. Lay all the biscuit in one run on two or three sheets.

Sprinkle with icing sugar

Bake in warm oven (180°C or 356°F) for about 14 minutes.

When finished, and when all biscuits have rised and browned...

...take the sheet out and let cool. Use it for a charlotte or with cream tea.