Preheat your oven to 170°C/ 338°F
In a pan, toast your almonds and hazelnuts then leave them aside to cool down. Once completely cold, roughly chop them into chunks.
Beat your egg whites to stiff peaks and gently add the icing sugar. Add your chunks of almonds/ hazelnuts and quickly blend the preparations together.
Using a spoon, shape your cookie dough and put it on an oven tray lined with baking paper.
Bake for 12-15 min or until the cookies are nicely golden on top.