Preheat your oven to 165ºC.
Sieve the flour into a large mixing bowl. Add the butter, egg yolk, sugar and salt. Knead until you have an uniform and soft dough.
Divide dough into three even parts (it is easier to roll out in three pieces).
Lightly flour a clean surface and roll dough out to 4 mm thick.
Use a round cookie cutters to cut the dough.
For the hole in the middle you could use the wide end of a piping nozzle (we just used some cookie cutter in flower shape).
Carefully transfer the cookies to a lined baking tray.
Decorate some cookies with shaved almonds and some with coarse sugar before putting in the oven.
Bake the cookies for 10–12 min, until very lightly coloured on top.
Remove from the oven and place on a wire rack to cool.
To hang the cookies on the tree, take 30cm long pieces of ribbon, tie and then loop through the hole in the centre of each cookie.