In a bowl mix together the cocoa, sugar and oil then add the egg one at a time and mix. Lastly add the vanilla extract.

In a separate bowl mix the all purpose flour, baking powder and salt then add all together to the cocoa mixture. You may use a rubber spatula to mix properly.

Cover the dough and place it the fridge for 1 hour to firm the dough.

When it is ready. Preheat the oven at 175 degree C.

Bake it for 12 minutes and then transfer to wire racks to cool down.