Combine the Flour, Cocoa, Sugar, Baking Powder, Baking Soda and Salt in a large bowl.
Take 1 Cup of Milk and add 1 tbsp White Vinegar to it. Set aside for 15 minutes.
Meanwhile, prepare Black Coffee with 2 tsp Instant Coffee and 1 Cup boiling water.
Add the Vanilla Essence, Eggs, Vegetable Oil, Black Coffee (Hot), Milk and Vinegar solution to the flour mixture in the bowl.
Beat the mixture on medium speed with a hand mixer for 2 minutes. The mixture will be of thin consistency.
Preheat the oven at 160 degree centigrade for 20-25 minutes.
Meanwhile grease the cake tin with butter and dust it with flour.
Pour the batter in the cake tin and tap gently to remove the bubbles.
Bake at 160 degree centigrade till the cake is done - a toothpick inserted comes out clear. It took me approx 1 hour 20 minutes.
Remove from the oven and let it cool completely at room temperature.
For the thick Glaze take heavy Cream and Milk Chocolate in the ratio of 1:1 (1 part cream, 1 part chocolate).
For the pourable Glaze take heavy Cream and Dark Chocolate in the ratio of 2:1 (2 parts cream, 1 part chocolate).
Heat the heavy cream in a pan till it comes to a boil.
Turn off the gas and add the finely chopped chocolate and mix well till you have smooth mixture.
For the thick glaze, pour over the cake and spread. For the pourable glaze, use a piping bag and design as desired.
For a Eggless version instead of the sour milk, add 1/2 cup milk and 1/2 cup yogurt - All at room temperature. Also reduce the qty of black coffee to 1/2 cup instead of 1 cup in the original recipe. All other ingredients remain the same.