1st mixture: Whisk 4 egg yolks with 3 whole eggs. Add 1 cup sugar, 8 tbsp oil, 1 cup flour and the yoghurt with the baking soda. Divide this blend into 2 parts, one needs to be smaller than the other.
2nd mixture: To the smaller mixture, add the cocoa.
3rd mixture: Whisk 4 egg whites into hard snow with the remaining 1 cup of sugar, pouring it in gradually. Add the flour to the mixture.
Coat a cake form or tray with oil and flour everywhere. Pour in the brown mixture first, then the white and sift cocoa through a sieve to completely cover the white mixture.
On top of the cocoa, pour in the yellow mixture. Bake in a preheated 302°F (150 °C) oven for 35-40 minutes. After removing, leave it to sit for 5 minutes and then remove it from the form.
Sprinkle the ready tricolor cake with powdered sugar. Enjoy!