1st: For the mould: I used non greased angel food cake mould. You can use any big mould you have preferably movable base other wise you can put parchment paper as a base. Do not grease the sides

The preparation of ingredients: separate the eggs, scale the 110 ml of milk add 2 tsp vinager and let stand (if you don't have butter milk) scale the sugar separately 110g+110g. Scale 200 g flour ▶️

And take out 2 tbsp. And only at this point add to the flour 1/2 tsp salt and 1/4 tsp sodium bicarbonate. Scale 110 ml vegetable oil. Measure 2 tbsp cacao. .. Now start preparing then making the cake,

Scale the buttermilk or the milk & Add 2 tsp of vinager to the milk

Measure 2 tbsp cacao. And scale 200g of flour.

Take out 2 tbsp of flour from the 200 g. (The 2tbsp cacao and the 2 tbsp flour will be added to the 2 parts of the batter after dividing it into half)

Leave for later the 2 tbsp of cacao and the 2 tbsp of Flour

And only at this point Add to the flour 1/2 tsp salt and

1/4 sodium bicarbonate. Now you can start making the cake

In the bowl of a free Hand mixer.. Or Using an electric hand mixer put the egg yolks

Add sugar

Mix

Add vanilla and continue mixing until they become pale

Adding the oil

While the mixer is on high, Add the oil in a thin stream

Sift the flour over the egg-sugar-oil batter

And fold in

Then add the milk and fold in

Egg whites. Add cream of tartar (if you have. Or a pinch of salt) and start mixing on medium until frothy.

Then start adding the sugar ((the other 110 g). Add the sugar slowly 1 tbsp at a time. Like making meringue

Until they are firm and shiny

Fold them in the batter. ..

Split the batter into half. Add the reserved tbsp of flour to one

And the 2 tbsp of cacao to the other

You can spoon the 2 mixture as you like

Cut away very thin layer all around

This is one result

But I am doing it the French way. I use a piping bag that will give a different result.

How to make a marble cake

Make a Marble Cake