You can find the recipe here (in Swedish).
200 g dark chocolate (70%)
25 g butter
0.5 dl white sugar
Break the chocolate into small pieces and put them in a bowl set over a pan with a centimetre of barely simmering water. Add the butter and allow both to gently melt. Stir occasionally. Separate the eggs into yolks and whites. Add a pinch of salt to the egg whites and whisk to the soft peak stage. Whisk egg yolks and suger, then pour the mixture into the melted chocolate. Mix gently together chocolate mixture and egg whites. Refrigerate for a couple of hours.
Thick and rich of chocolate flavour! Serve straight out of a big bowl.