Mix the egg white with the salt, the butter, the icing sugar and the flour. Now blend this till smooth. Then pour it on a silicon sheet and spread it with a pallet knife. After, bake it at 150 degrees Celsius for 15 minutes till golden brown. Now let it cool down completely. Then remove the silicon sheet and break the tuillle in smaller pieces. Transfer it into a bowl and crunch it a bit more. For every gram of tuille bits you need to add 1 gram of melted dark chocolate that’s 35 degrees Celsius. Mix this well. Then transfer it on a silicon sheet and put another sheet on top. Now like before us a rolling pin to roll out the feulletine into a thin sheet. Then let it set out of the fridge. After remove the top sheet and gently portion the feulletine into the desired shape. Then keep them dry and covered for later.