In a deep bowl, pour the melted butter, cold sugar, grated chocolate. Beat everything with a mixer until you have a smooth cream. Add the coffee that you've dissolved in 1 tbsp hot water ahead of time.
Add egg yolks, one by one, while continuously whipping. Next, mix in the egg whites gently. Mix in the breadcrumbs with a wooden spoon. Pour the mixture into a greased form with removable sides and bake in a moderate oven until crisp. Carefully remove the sides of the form.
Melt all the ingredients for the topping in a pot on the stove, stirring until homogeneous. Pour the warm glaze over the now cooled chocolate cake. Leave for 2-3 hours to cool before serving.