675g dark chocolate
625g caster sugar
Melt the chocolate and butter together and set aside to cool.
Preheat the oven to 160°C and line a 127cm spring-form pan with foil.
Beat the eggs and caster sugar using an electric mixer until the mixture expands.
Fold in the chocolate and butter mixture, and place in the pan. Bake in a bain-marie with water halfway up the sides of the tin for an hour. Switch off the oven and allow to cool before removing.
This cake is very rich but not too sweet, and is best served with a complement that cuts the richness, like basil and berry compote with mint ice cream or ginger white chocolate sauce with candied fruit and nutty praline for some added texture.