In a mixing bowl take sugar and oil and mix them well.
Add milk to it and again whisk it so that all three combines well.
Add vanilla essence and whole wheat flour to it and whisk it well to make better lump free.
Now divide the mixture in two equal parts. and add cocoa powder to one part. and mix it well.
To make cake in cooker preheat cooker. or preheat oven at 180 degree C if using oven. Grease the cake pan and dust it with little flour.
Now pour 1 teaspoon white batter to the pan and tap it twice, now pour 1 tsp brown batter and tap twice. Now repeat the process with both the batters.
To make marble design take a toothpick and from all the sides make lines towards the center. it will give you marble design.
Now place the cake pan in preheated cooker or oven.
In cooker place a stand and over it cake pan and cook it for 40 minutes without whistle on the top.
For over cook it for 40 minutes.
Now allow the cake to cool completely and then cut it into slices and serve.
Serve the whole wheat cake and store the leftover in an airtight container.
