Beat the sugar with eggs in a container until they become almost snow-like. Then in a separate bowl, put half a cup of whole wheat flour and half a cup of dark flour - add the oil and baking powder.
Slowly add them to the eggs and sugar. Grate the apple in another container, having peeled it ahead of time and add the walnuts and cornflakes. Add the remaining flour - and whole wheat and dark flour and mix well. Combine everything and mix gently.