Mix baking powder, baking soda, salt, sattu and wholewheat flour together and sift/sieve it three times.At this point put the oven for 10 mins preheat.
Next mash banana in a deep bowl, add jaggery , curd and oil and beat them together till they are evenly mixed.
Add vanilla essence to this this and gradually mix the dry flour mixture into this bowl.
Use a spatula to fold all the ingredients so they mix together. You might need to add milk at this point as the batter gets dry however take care not to over mix the batter.
Now mix chopped walnuts and choco chips too. Grease the baking pan and pour the mixture in the centre of the tin and then tap it to make it even.
Bake it at 180 degrees for 25 mins and then do a tooth pick test. If the tooth pick comes out clean , let the cake sit for another 10 mins before you take it out. Enjoy it with some warm milk or just like that.