Method:

Seperate the eggs, placing the whites into a roomy bowl.

Break the chocolate into small pieces and put them into another roomy bowl set over a pan with a centimetre of barely simmering water. Add the butter and allow both to gently melt. Stir occasionally

In the meantime, add a pinch of salt to the egg whites and whisk to the soft peak (floppy) stage. In a seperate bowl, break up the yolks.

When the chocolate and butter have melted and have been allowed to cool for a couple of minutes, stir in the yolks.

Cut and fold in the whites in three batches until seamlessly combined. Pour into ramekins and refrigerate for a 5 hours to set