Method of preparation:
In a blender, beat the beets, the whites, the whole egg and the oil. Beat a lot, so that there are no pieces of beets, about 4 to 5 minutes. Preheat the oven to medium temperature. Transfer the mixture to a bowl, add the sugar, mix and gradually add the flour while stirring with a fuet. Add the yeast. Pour the mixture into a pan greased with oil and sprinkled with cocoa powder (do not use flour to sprinkle as it turns white and disrupts the color of the cake afterwards). Place in the oven for about 45 minutes or until the toothpick comes out clean.