Sift flour and baking powder together.
In a bowl put cocoa and 1/2 cup water and mix well, keep aside.
In a big bowl beat sugar and butter till it's creamy add one egg at a time and beat well till all done add dry ingredients, oil and cocoa mixture mix well.
Pour on a greased baking tray, bake on 170C.
When cake is done let it cool a little then slice half horizontally.
Apply cream and place the other half.
Sprinkle black coffee and pour cream or chocolate ganache.