1. Preheat oven to 180C.
2. In a mixing bowl, whisk unsalte butter with Fleur de Sel until creamy.
3. Add in powdered sugar and whisk until homogenous and creamy.
4. Add in egg white. ( The mixture may curdle a little but it will smoothen out after flour is added.
5. Add in flour and mix until well combined.
6. Roll the dough in between 2 sheets of plastic to 0.3cm thick. Chill in the fridge for 30mins or more. Cut the dough into desired shapes using a cookie cutter. Sprinkle with coarse grain sugar.
7. Bake at 180C for 10 -12 mins or until golden brown.
8. Cool down and store in air tight container.