Mix all the ingredients in a bowl.
Reserve the dough in the fridge for about 15 minutes.
Spread the dough 5mm thick on a baking sheet of parchment paper (simpler and faster to clean + we can reuse it to bake cookies)
Cut your biscuits with pieces and put them on a sheet of parchment paper.
Gather the remaining dough and repeat the operation.
Mix the egg yolk with 2 tablespoons of water and brush the biscuits with a brush.
Preheat your oven to 180 ° C. Bake 12-14 minutes. Reserve and put in a metal box.