Heat the oven to 180 degree celsius.
Grease two 9 inch cake dishes with butter and then dust with cocoa powder.
Take a bowl put in the butter and sugar together, stir well. Next add the eggs one at a time, whisk this mixture properly until it is finely blended together. Then put in the vanilla extract and mix well.
In a separate bowl, add in the food colouring along with the remaining cocoa powder to form a paste. Put this paste into the butter mixture and combine it well together.
Sift the dry ingredients and keep aside.
Make 2 batches and alternately pour buttermilk and dry ingredients into the butter mixture. Mix the vinegar into the last batch of the buttermilk before pouring it into the batter.
Now mix it well together so that all the ingredients are well incorporated.
Divide this batter equally and pour into the two greased dishes. Bake for a time period of 20-25 minutes.
Once the cake is cooked, let it cool off on a wire rack.
To make the icing: beat the butter and cream cheese together using an electric mixer in a large bowl.
Slowly add in the powdered sugar and continue mixing till it is smooth and creamy.
Finally pour in the vanilla extract and mix again. Keep aside.
Start assembling by transferring 1 cake and placing it on a serving plate with its flat side facing downwards.
Pour a cup of icing onto the cake and spread it uniformly with a spatula.
Then transfer the second cake on top of the first layer in the same manner. Cover the top and sides of the cake with the remaining icing.
Serve after refrigerating it for some time.