Line a cake tin (approx. 20 cm) with baking paper.
Melt the butter in a pan, allow to cool slightly. Mix the flour, salt, sugar, cocoa powder and baking powder in a bowl. Add the eggs, butter and cream, mix. Transfer the mixture to the prepared tin.
Press the chocolate bars into the cake mixture.
Approx. 1 hr. in the lower half of an oven preheated to 180°C. Remove from the oven, allow to cool slightly, remove the cake from the tin and leave to cool on a rack. Dust the cake with icing sugar.