Beat the egg whites, add the sugar and mix again until they harden. Add the water and the yolks rubbed with oil. Mix with a spoon from the bottom up. Gradually add the flour mixed with cocoa and baking powder. Homogenize. In a greased tray, lined with flour or baking paper, put the composition and bake for 30-35 minutes. After cooling, the top is cut into 2.
Mix the soft butter with the powdered sugar until it becomes creamy, then add the melted chocolate with 2 tablespoons of milk and mix. Add the liquid cream and rum essence and mix. Leave to cool until assembled.
Mix the ingredients in a kettle and boil until the sugar dissolves.
7. Break the chocolate into pieces, mix with the whipped cream and butter and keep it on the fire until it is homogeneous.
The top is cut into 2 equal sheets. A sheet is placed on a tray, syruped, not too much, spread the cream, cover with the second syrup sheet and leave to cool. After an hour remove from refrigerator and cover with icing, leave to cool, then proportion and decorate with a word of whipped cream!