How to make
Beat 4 egg whites to snow, then add 1/2 cup sugar and 2 tbsp oil. Add 1/2 cup flour by sprinkling it on and stir with a wooden spoon only.
Beat the yolks and remaining 3 eggs with 1 cup sugar and 4 tbsp oil. Once beaten, sprinkle on 1 cup flour and stir the mixture with a wooden spoon. Set aside 1/3 of this yellow mixture and add the cocoa to it. Stir until the mixture gets colored.
Pour the brown mixture into a buttered form. Sprinkle cocoa on top so that there's no spot without cocoa. Then pour on the white mixture and sprinkle with cocoa again. Finally, pour on the yellow mixture.
Bake in a preheated 340°F (170 °C) oven.