For preparing cocoa cake, first sieve flour, baking powder & baking soda. Keep this aside.
Whisk eggs. Add butter & sugar. Mix thoroughly.
Mix cocoa powder & milk.
Add flour mix and milk solution alternatively and mix thoroughly.
Add vanilla essence, salt & vegetable oil.
Divide the mix in 2 pans(9 inch) and bake for 350 degrees for 30-35 min.
Method for frosting:
1)Mix butter & shortening thoroughly.
Add the remaining ingredients & beat thoroughly.
Apply on cake using a cake spatula.
Decorate with Nutella hazelnut spread.