Mix together milk, oil, vanilla, unsweetened cocoa powder, sugar and the pinch of salt until the mixture thickens.
Remove 1+ 1/2 cup of this chocolate mixture, save it for later.
To the rest of the chocolate sauce, add the eggs, flour, and baking powder.
Pour the batter in a cake tin that is already buttered and floured or lined with parchment paper.
Bake for 30 to 5 min in a 175C / 347F preheated oven.
Once out of the oven, make many small wholes using a toothpick and add coffee or chocolate milk.
Cover the cake with the remaining chocolate sauce you saved at the beginning.
Enjoy!
