Preheat the oven to 180C/350F/Gas 4. Grease and line 8inch cake tin.
2.Take a bowl, sift flour, cocoa powder, baking powder and baking soda.Then add sugar to it and mix everything well.
3.Add eggs, milk, oil and vanilla extract and using an electric whisk, beat the mixture until smooth and well combined.
4.Mix instant coffee powder to the hot boiling water and stir well and keep aside.
5.Add the coffee water to the batter, a little at a time, until smooth. (The cake mixture will now be very thin.)
6.Pour the mixture into the greased tin and bake in the oven for 25-40 minutes, or until the top is firm to the touch and a skewer inserted into the center of the cake comes out clean.Remove the cakes from the oven and allow to cool completely, before decorating.