Chocolate marble cake

An easy and old-time-classic cake today. I made it for the school of one of my kids to sell and fund their trip. I chose this cake as many people like this cake and it is true that it disappeared immediately.
The best compliment was the one of my kid that when he saw that the cake was sold immediately, said the sweetest thing to my husband : "Mum has something magic in her hands that makes everything that she cooks delicious" .... Am I not lucky with such kids?

Ingredients
1 cup of butter or margarine
2 cups of sugar
1 vanilla
4-5 eggs (depending on how big they are)
3 1/2 cups of self-raising flour
1 cup of milk
4 spoons of cocoa powder
2 spoons of icy sugar
1/8 teaspoon of bicarbonate

 

Procedure
Soften the butter and warm the milk in the microwave oven (separately). Then add to the butter the sugar, the eggs, the flour and the 2/3 of the milk.

 Mix well for about 4-5 min.
Pour 2/3 of the mixture in a buttered cake mold (here in two small ones).

In the remaining dough, mix the cocoa powder, the icy sugar, the bicarbonate soda and the remaining milk.
Pour on top of the first dough.
Use a stick (whatever you have available) and with round movements mix slightly the two doughs like in the photo. 

Bake at 180 degrees of Celsius and fan for about 40 min (in my case) or until you use a knife and it comes out clean of the dough.
Leave the cake to cool for about 10min and get it out of the mold.
I hope that you will have time to admire your result like in the photos as it might disappear fast. Sprinkle some icy sugar on top to make it look even nicer (I did not do this time as it was not practical for the school).
Nice to serve at tea time and for breakfast.
Dedicated to a friend Tony, also, that he is German and told me once that I do it exactly as his mother does it and it is also a great compliment for me!