Preheat the oven at 180°C.
In a bowl mix the butter with sugar until it's smooth.
Add the egg and vanilla extract.
In a separate bowl whisk the flour with baking powder and salt.
Gradually add the dry ingredients to the wet ones and mix until it's smooth and fully combined.
Place the dough on the counter dusted with flour and divide it into 2 batches, roll it out and shape it as you like.
For the medium and large cookies I baked them 8-10 minutes, for the small ones 6-7 minutes, until the edges are slightly golden brown.
Let them cool on the cooking sheet until firm enough to transfer them and before decorating.
