Firstly, in a large mixing bowl take condensed milk and butter.
beat in one direction till the mixture turns smooth and fluffy.
also add maida, cocoa powder, baking soda, baking powder and salt.
then fold gently. add vinegar, vanilla extract and warm milk.

Smooth dropping consistency. transfer the cake batter to a cake mould. bake the cake at 180 degree celsius for 25 minutes. cool down the cake.

For chocolate frosting:
in a large mixing bowl take take butter and butter and beat.Then add cocoa powder, powdered sugar, vanilla extract add cold milkk. beat till the mixture turns smooth and spreadable.

Spread the generous amount of prepared chocolate frosting.
then place baked cake.spread the frosting. at last cut the cake to desired shape and serve.