First, melt the butter together with the chocolate in a bowl over steam until everything has a liquid consistency.
In another bowl, mix the nuts with the sugar. Add the hot chocolate and add the whiskey. Mix everything well and chill in the refrigerator for a few hours until a very solid (malleable) mass is obtained.
Take small portions from it with a demitasse spoon, form them into small balls and roll them in the coconut flakes.
Store the whisky balls in a cookie tin in a cool place.