How to cook
Beat the eggs with the sugar in a bowl with a mixer. Add the oil, milk and vanilla. Stir well.
In an oiled and floured cake form, first pour in the white mixture, then the cocoa one on top and use a wooden skewer to make spiral movements for the decoration.
Bake in a preheated 356°F (180 °C) oven about 50 min. to a dry toothpick. Take it out and optionally sprinkle with powdered sugar, although it's plenty fluffy and tasty as is.