Melt the dark chocolate and butter in a bain-marie. Separate the yolks from the egg whites and beat the latter until stiff. Add to the chocolate and melted butter, off the heat, the sugar, the egg yolks one by one, the flour, the cornflour and the baking powder. Then, gently fold in the beaten egg whites. Pour the batter into a springform pan and bake for 25 minutes in a preheated oven at thermostat 4 (120°)
During the cooking, break the 200 g of cooking chocolate into small pieces in a bowl, and bring the liquid cream to the boil. As soon as it boils, pour it over the chocolate and cover. After 3 minutes, mix to obtain a smooth preparation, then leave to cool.
When the cake is cooled, cut it in half to fill it with the chocolate ganache cream. Coat the top and decorate with some Easter chocolates!
This very "chocolate" cake can be made for other occasions than Easter:just change the decoration!