Sift the all purpose flour along with baking powder and chocolate powder
Separate egg yolk and egg white
Add the egg yolk, walnut to sifted ingredients, mix well
Add the brewed coffee, milk little by little until the mixture becomes paste
Beat the egg white until it becomes frothy
Add sugar to the egg white and beat further until soft peak
Fold the egg white into the cake mixture - this will make the mixture light and fluffy
Pre-heat the oven to 180°C
Pour the mixture into a greased cake pan
Bake for 25~30min
Allow the cake to cool