Preheat oven to 180 degrees C. Grease and dust a 7X11 inch rectangular baking dish (glass/ceramic or tin). Brew the coffee and allow it to cool.
Sift the flour, baking powder and cocoa into a bowl. Add the butter, sugar, eggs and vanilla extract and using a whisk beat everything together till the mixture is smooth and without any lumps. Add 3 tablespoons of the prepared strong coffee (cooled) and whisk everything well.
Pour the batter into the prepared baking dish and level off the surface. Bake for 30-32 minutes or till the skewer inserted comes out clean.
While the cake is baking, prepare the coffee sauce. Mix the cornstarch with 2 tablespoons of the prepared coffee till no lumps remain. Transfer this mixture to a saucepan, add the remaining coffee, cream and sugar and whisk everything together. Simmer gently for approximately 2 minutes or till the sauce thickens. Remove from heat and pour into a serving dish/sauce jug if you wish. Cover with clingfilm to prevent the cream from thickening.
When the cake is out of the oven and still hot, carefully punch out 6 rounds using a 9cm round cookie cutter. Alternatively you may also cut the cake into squares. Transfer each portion into a serving bowl or plate and pour the prepared coffee sauce over it. Serve immediately. You may also serve it with some vanilla or chocolate ice cream on the side. Tastes simply divine!