Combine Nutella, maida and curd in a large bowl and mix. Whisk well to get a lump-free batter.
Grease a rectangular baking tray with butter and line with parchment paper. Pour the batter into it.
Bake at 180 degrees Celsius for 25-30 minutes. Baking time depends on your convection. We suggest you remain alert after 25 minutes. Check with a toothpick. If it does not come out clean, you may bake for a few more minutes.
Remove from the oven and allow to cool completely.