4 large eggs, at room temperature
250 g) granulated sugar
150 ml milk, at room temperature
200 ml sunflower oil
1 tsp vanilla extract
300 g flour
1 tbsp baking powder
25g cocoa powder
Preheat the oven to 180C/350F. Butter a 23cm/9in cake tin
Combine and mix flour and backing powder.
In a large mixing bowl, combine eggs and sugar. Using a hand-held electric mixer or wire whisk beat until the mixture is creamy and light in color.
Add vanila exract, oil and milk , continue beating until well blended.
add the flour mixture to the wet ingredients and beat just until the batter is smooth.
Divide the mixture into 2 equal portions. Keep one portion plain. Add cocoa powder into another and mix well (add 1 tablespoon milk or water if you find that the chocolate mixture became harder).
heaped 2 tablespoons of plain batter into the middle of the baking pan. Then scoop 2 tablespoons of cocoa batter and pour it in the center on top of the plain batter. Continue doing this until all the mixture has been used.
Cook for 40-50 minutes, until the cake is cooked through, a skewer inserted into the centre should come out clean. Turn the cake out onto a wire rack to cool before serving.