Melt butter n chocolate in the microwave. Keep aside

Sieve maida n baking powder n cocoa powder

In a bowl add yogurt, castor sugar beat well till they become creamy in texture. Add condensed milk mix properly

Add maida mixture to it mix it slowly by cut n fold method add chocolate mixture n Nutella to it

Preheat oven at 160 degrees

Pour the batter into the tin. Tap it well. Put this tin into the oven n bake for 25/30 mins

When cake is done dizzle nuttella over it