How to make
Beat the eggs with the sugar and yogurt. Then add the vinegar and baking powder and mix well. Add oil and mix again.
Then add the flour, which needs to be sifted. Stir by hand. When the mixture is ready, put 2/3 of it in the form. Then add the cocoa to the remaining mixture and stir.
Pour the cocoa mixture into the other mixture. Bake at 360°F (180 °C) until tender. Take it out from the oven and sprinkle with powdered sugar.
The powdered sugar is optional.