1. Preheat the oven to 180°C/350ºF.
2. Mix the Egg whites and flavoring well.
3. Whip the mixture to stiff peaks.
4. On a baking tray, place baking paper and spread a little oil.
5. Bring the mixture to the tray, spreading it gently without crushing it, and bake for about 5 minutes up and down.