Marble Orange and Cocoa Chiffon Cake

Marble Orange and Cocoa Chiffon Cake
( Orange chiffon cake adapted from jeannie tay with my marble effect adjustment)

Ingredients:-
5 large eggs yolk
150g flour
100g caster sugar
2 tsps baking powder
1/2 tsp salt
orange zest from 3 small oranges
105g vegetable oil
150 g fresh orange juice (about 2 large oranges)
1 tsp pure vanilla extract

6 large eggs white
50g caster sugar
1/2 teaspoon cream of tartar

For marble effect
3 tbsp cocoa powder
1/3 mixed batter

Instructions:

1. Zest the oranges and squeeze out juice. Measure out 150g and set aside.
2. Sift together the flour, baking powder. Set aside.
3. In a large mixing bowl, place the yolks, oil, salt, vanilla extract and 100g sugar and beat with a hand whisk until combined and sugar has dissolved.
4. Beat the egg whites until frothy before adding cream of tartar. Continue beating until fine foams then gradually add in the 50g of sugar. Beat to stiff peaks.
5. When the meringue is almost done, add in the orange juice to the yolk batter followed by the flour and whisk quickly to incorporate until mixed.
6. Add 1/3 of meringue into the yolk batter and mix well with a hand whisk to lighten the batter. Add another 1/3 and mix till combined. Lastly add the final portion and whisk briefly to combine before switching to spatula to scoop batter from bottom and fold up until no more streaks of yolk batter can be seen.
7. Pour into 22" pan with alternate chocolate mixture and white batter and drip any pattern you like then use a fork to run through the batter from bottom to top in circular pattern and tap on the table top to remove bubbles and also to even out the batter.

8. Bake in preheated oven at 160C and place a small bowl of hot water at the corner of the oven for 60-70 minutes or until cooked. Invert immediately to cool completely before unmoulding.