How to make
Sift the flour and cocoa. Add the sugar and baking powder. Stir and add the milk in a thin trickle. Beat well until you obtain a thick cake batter.
Pour the mixture into a dry tray with a nonstick coating and put it in a preheated oven.
Bake until the cake is ready (check with a toothpick - when you poke the cake with it it needs to come out clean).
Sprinkle the ready cake with powdered sugar and lemon zest.