How to make
Beat the butter with the powdered sugar. Add the yoghurt with the baking soda and flour. Knead a soft dough. Make small balls from it, about the size of an acorn.
Heat the cookie maker. Place a doughy ball in each holder and close the cookie maker. Bake at moderate heat on both sides for no more than 1 min. (they burn quick). Do this for all of the dough.
Cut off the ends of the buttery cookies.
In a pot, pour in the milk, sugar and flour for the cream. Stir until thickened. Leave it to cool.
Beat the butter with the powdered sugar and add the cooled milk cream to it.
Add the vanilla, walnuts and optionally - the cut off ends of the cookies. Stick the cookies in pairs with the resulting mixture. Dip each acorn in melted chocolate and coconut flakes or walnuts.