A plain chocolate cake used as a blank canvas to finish as you wish.
Mix the flour, baking powder, cocoa powder, salt and sugar together.
In a jug add the water, oil, coffee and vanilla - mix until the coffee dissolves.
Whisk the liquid into the dry ingredients ensuring all lumps are gone.
Pour the batter into a lined or greased cake tin. Cook at Gas Mark 4 for 40-50 minutes. When the cake is done, a skewer inserted into the middle of the cake should come out clean.
Allow the cake to cool in the tin before removing.