Beat eggs with sugar until frothy. Mix the flour and baking powder, add to the egg and sugar mixture together with the oil and milk. Process into a smooth batter.
Halve the dough. Mix one half with cocoa powder and 1-2 tablespoon milk. Place the dark dough on a deep, greased baking sheet / drip pan (approx. 30x33x4.5 cm) and spread evenly.
Bake in a hot oven at 170 ° C for about 8-10 minutes.
In the meantime, prepare the cream filling: Mix the flour with milk in a saucepan while cold, add desiccated coconut and sugar and bring to a thick cream while stirring.
Take the dark dough out of the oven, the top layer should no longer be runny. Spread the cream evenly on top and pour the light-colored dough half over it.
Bake everything together for another 30-35 minutes.
Cover the still warm cake with the dark, melted chocolate icing and sprinkle with desiccated coconut.