Sift the All purpose flour and cocoa powder well. Keep it aside.
Take a bowl, add butter, condensed milk and beat well.
To the butter - condensed milk mixture, add baking soda, baking powder and mix well.
Now add the sifted flours to the above mixture and blend it well by cut and fold method or using electric blender.
Finally add the coca cola and mix well.
The cake batter is ready.
Place the butter paper in the greased cake tin.
Pour the cake batter into the pan.
Pre-heat the oven at 230 degree celsius for 3 minutes.
Then bake the cake at 150 degree celsius for 35-40 minutes.
Check the cake in between. The temperature and the timing varies from oven to oven.
Insert the toothpick and if it comes out clean, then the cake is ready.
Allow it to cool. Then remove it from the cake tin by inverting it on the plate.