Beat the egg with sugar into a foam. Gradually add oil, milk and other ingredients. (Note: for less sweet taste, use half the sugar).
Prepare a baking tray (7 x 12 in), grease it with oil and sprinkle with flour. Put the prepared dough on the tray and bake in a pre -heated oven at 350 °F / 175 °C for about 25 minutes. Let the cake cool.
Prepare the filling. Mix sugar and pudding powders with the milk. Cook a thick pudding and let it cool. Beat the butter into the foam and gradually add cool pudding. Lay the filling on the cold cake and sprinkle the top with grated chocolate. Enjoy your cake!