In a bowl combine both flours, salt, corn starch and baking soda. Whisk.

In a separate bowl, add both types of sugar and add the melted butter while whisking. Add one egg at a time followed by the egg yolks. Once it gets homogeneous, add the flour mixture. Add the chocolate and walnuts

Chill for at least 45 minutes covered in plastic. The longer you chill them, the taller they will be.

Bake at 220 °C for 10 - 13 minutes or until golden brown. Use baking paper.