When there are Easter eggs left and you don't know what to do with them !
Mix the butter with the sugar. Add the egg and the vanilla extract. Then, add the salt, the flour, the baking powder to form a ball with the dough.
Make littles balls (about 16) with the dough and put them on a baking paper. Bake for 25 minutes at 280°F (140°C).
Take the cookies out of the oven and add the eggs on top. Leave to cool down during about 10 minutes.
That's it !