Eggs - 4 large, at room temperature
Granulated sugar - 1 cup (increase to 1½ cups for a sweeter cake)
Milk, at room temperature - 1/2 cup
Refined Oil - 3/4 cup
Maida /All purpose flour - 2 cups
vanilla essence - 1 tsp
Baking powder - 1 tsp
Baking soda - 1/2 tsp
Dark cocoa powder - 2 tbsp.
In a large mixing bowl, with a hand beater or wire whisk beat oil and sugar. Add egg and continue beating until its well blended. Beat until the mixture is creamy and light in color.
In a separate bowl, mix flour and baking powder. Add the Maida mixture and milk alternatively to the wet ingredients(egg,oil,sugar) and combine until the batter is smooth and the dry ingredients are thoroughly incorporated. (Do not over beat to prevent air pockets from forming in the batter). The batter should be of medium consistency, not too thick and not too watery.If the mixture is too thin, add a little more flour.if its too thick add little more milk.
Divide the mixture into 2 equal portions. Keep one portion plain. Add cocoa powder into another and mix well. Grease 9" round cake pan with oil. Scoop 3 heaped tablespoons of plain batter (you can also use a ladle that would hold 3 tablespoons) into the middle of the baking pan. Then scoop 3 tablespoons of cocoa batter and pour it in the center on top of the plain batter. Do not stop and wait until the previous batter spreads. Do not spread the batter or tilt the pan to distribute the mixture.It will spread by itself and fill the pan gradually. Continue alternating the batters until you finish them.
Preheat the oven to 180 degree C. Bake in the oven for about 45 minutes. Do not open the oven door at least the first 20 minutes or the cake will shrink and will not rise.
To check if the cake is ready, insert a toothpick into the center. It should come out clean when ready. Remove from the oven. Keep it for cooling. When cool run a small thin knife around the inside of the pan to loosen the cake, then invert the cake onto a pan and cut into pieces to see the surprise......:)