Step by step recipe:

1. 3 min.
   Preheat the oven to 150°C (300°F).
   
   Put 60 g egg white and 100 g icing sugar into a food-processor bowl.
2. 7 min.
   Beat to mix thoroughly, then place the bowl over a pan of water kept at a bare simmer.
   
   Beat the mixture until the temperature reaches 50°C (122°F), using a thermometer to check this.
3. 5 min.
   Return the bowl to the food processor and beat on maximum speed for around 5 minutes.
4. 
   You will notice that the mixture is not as light as for a classic meringue, but much creamier.
5. 5 min.
   Pipe your meringues onto a sheet of cooking parchment using a forcing bag.
6. 2 min.
   Dust with a little cocoa powder if you wish (purely decorative).
7. 45 min.
   Bake for 45 minutes...
8. 
   ...and prop the oven door open with a wooden spoon to allow the steam to escape.
9. 10 min.
   Leave to cool on a wire rack.