Preheat oven to 180 C. Grease a 9 in / 23cm cake tin.
Beat butter until light and fluffy with electric beater. Add sugar and beat for another minute. Gradually add the beaten eggs, coffee water, alternating with the self-raising flour and beating until the mixture is smooth and light. Tip into the prepared cake tin.
Bake for 30 to 35 minutes, or until skewer inserted into centre comes out clean.
Place all the syrup ingredients in a pan and heat until the sugar has dissolved.
Prick holes all over the cake and spoon the coffee syrup over the cake while still warm.
For the coffee sauce: mix all the ingredients and heat until the sugar dissolves. Serve cake warm drizzled with warm coffee sauce.