Start by taking a bowl and put flour, baking powder, baking soda, custard powder and mix it well.
Take another bowl and mix together butter and sugar till light and fluffy.
Add the condensed milk and beat well.
Gradually put the flour mixture into the bowl of wet ingredients and mix well after each addition.
Add mango pulp and mix till the mixture becomes light and fluffy.
Lastly add cashews and kismis and mix it well.
Batter is ready to go in a greased tin.
Grease the baking tin with butter. Then sprinkle about a tablespoon of flour. Now swirl the pan so it will stick to greased surface (all over pan and also around the edges). Now invert the pan over a sink or garbage and tap it gently with your hand to remove excess flour.
Pour the batter into the tin and Tap the pan on the countertop to remove air bubbles.
Sprinkle some melon seeds on top of the batter.
Bake in a pre-heated oven at 200 degree Celsius for 30 to 35 mins in the convection mode of a microwave oven.
Once baked insert a tooth pick or knife just to see if it is cooked properly or not. If the Knife comes out clean it means the cake has cooked properly.
Remove the cake from the tin after it cools a bit and then scratch the sides of the tin, invert it into cooling rack or tray and let it cool completely.
Slice and serve this Mango custard cake.
Notes: If top starts to get browned early during baking, then cover with foil or butter paper and continue to bake.