Eggless Marble Cake

This cake I have couple of times made before, but this time nailed it.
My daughter's school had asked to donate cakes and cookies for sale and proceeds got will go to some charity, It could be either store bought or home baked.
First I thought of Red velvet cake with cream cheese frosting, then the ingredients I was not sure as children in school have some food restrictions.
Then the previous day I went with family for a day outing to Bath.
Next day, the day I had to bake the cake to give it the next day.
I was damn tired, the baking went on postponing as I was tired from the previous day outing, as I had walked the whole city walking.
It was already evening, then I finally went to kitchen to bake and realised I have nothing for cream icing, now I had to think and bake a cake which still tastes good without frosting.
Then I thought of this marble cake, again I was too tired to look into my recipe dairy, but I did know the ingredients for the basic sponge cake.
Then I worked in my head to make changes to the recipe to make a marble cake.
The outcome was fantastic and people enjoyed and sad part many could not have to their heart's content as it was sold out, even after two days I was asked when are you making again.

Ingredients:
Dry Ingredients:
Cake Flour - 2 1/2 cups,
Baking Powder - 2 teaspoons,
Baking Soda - 1 teaspoon,
Salt - a pinch,
Granulated Sugar - 2 tablespoons.
Cocoa Powder - 3 tablespoons.

Wet Ingredients:
Condensed Milk - 400 grams tin,
Water - 1 cup,
Butter - Melted 1/2 cup,
Vanilla Essence - 2 teaspoons,
Vinegar - 2 teaspoons.

Method:
Preheat Oven at 170 degree celsius/gas mark 3.
Grease a round 8 inch baking tin.
Sieve cake flour, baking powder, baking soda and salt.
Add sugar, mix well and keep aside.
Mix all the wet ingredients and blend well.
Make a well in the dry ingredients, add wet ingredients and gently fold to mix well.
You can as well use a electric mixer for this.
Now make two portions out of the batter.
To one portion add cocoa powder  and mix gently.
First layer vanilla batter in the greased tin.
Top it with chocolate batter evenly and finally cover with vanilla batter.
To a toothpick or fork and make deep swirls to make marble design in the cake.
Bake for 40-45 minutes or until a tooth pick comes out clean.
Coo and enjoy!!!!!

Note:
To make cake flour either you can buy ready from super store or
Measure 1 cup plain flour, take out two tablespoons of plain flour from that measured 1 cup of flour and add 2 tablespoons of corn starch and mix well.
Like this you can make flour according to your needs.