Grease a cake pan and set aside. Preheat oven at 180c for 10 mins.
Take the chocolate and cut them into small chunks. Mix with 1/2 tsp flour and set aside.
Seive the flour, cocoa powder, baking soda, baking powder in a mixing bowl, mix well and set aside.
In a large mixing bowl, take curd and sugar, whisk nicely and mix well till the sugar is melted. Add vanilla essence, milk, oil and stir well.
Add in the flour mix and fold gently and make a smooth batter without lumps. Add the chocolate chunks and stir gently.
Pour the batter into the greased pan and bake the cake for 40 mins. Start checking from 35 mins. A tooth pick inserted should come out clean.
Remove it from the oven, let it cool down and invert it.
To make the chocolate frosting, take the butter, chocolate and sugar in a sauce pan and heat it for few seconds and switch off the flame immediately when the chocolate starts to melt. Add the cocoa powder and milk, mix well till both sugar and chocolate is melted completely and everything is combined well and smooth. Set aside. Your frosting is ready.
Now take the cake and evenly spread the frosting all over the cake with the help of a stapula or knife and finally dust the cocoa powder over the cake. Cut and serve.
