Sift baking powder,baking Soda,Cocoa powder and Flour and keep it aside.

Pre heat the oven to 350 degree F

Whisk Sugar and butter in big bowl until it becomes soft and smooth,the sugar should completely dissolve, there should not be any crystals in the mix. Add Egg onto this mixture and whisk in high speed until it becomes light. Add Vanilla essence and coffee powder too.

Add the dry ingredients onto the mixture and the yoghurt. Using a spatula mix it well. Pour the mixture onto a 9 inch Square baking pan. If you are not using a nonstick pan you should butter the pan and then dust it with flour.

Bake at 350 F for 35 mins, keep checking it after 25 mins, if the cake tester comes out clean then the cake is ready to take out of Oven. Let it cool.

Note : 1.Always use room temperature butter and egg. 2. if you are not so fond of coffee flavour, you can exclude coffee powder.