Beat the eggs, sugar and vanilla with mixer, then add the oil and soft and break up again. Slowly add the flour with baking powder. When the mixture is stirred in January divide into two equal parts, in one half put the cocoa and mix well. In a greased baking pan put one part of the mixture (tray me about 40h20 cm). Bake at 180C degrees until ready, then bake and cocoa mixture in the same way. A syrup is prepared with water and sugar with vanilla until it boils, stirring gently. Cream is prepared from 650 ml milk and one starch vanilla. Similarly straight and cocoa cream. 500 ml milk is put to boil, put the solution into the remaining milk starch stream and stir lightly sweetened to taste with sugar. In the pan put a little vanilla cream, to cover the bottom, top put cocoa base and gently syrup, then pour the rest of the cream of vanilla. Put the white base on the other and slightly syrupy, top pour cocoa cream. Once cool, you can decorate with sugar sticks or other of your choice.