Take milk, sugar, and custard powder in a saucepan and whisk it well until everything is mixed and there are no lumps.
Turn the heat on medium. Cook this mixture by stirring constantly. As soon as it starts simmering, scrap the sides and bottom of the pan using a spatula while stirring and make sure that custard is not sticking to the pan. Cook until it reaches the thick custard consistency. It took me about 3-4 minutes.
How to know the custard is ready? Check the consistency, using a wooden spoon. The thick custard will stick to the spoon, run a finger at the back of the spoon. See the line stay as such meaning, custard stay separated in that line. This is perfect.
Remove that custard to a bowl and let it cool down for 5-7 minutes. Then add mango pulp and cardamom powder.
Whisk it until everything is mixed. Once mixed, let it come to room temperature. It may take 30-40 minutes. Do stir occasionally every 5-10 minutes until it cools completely and make sure that it stays smooth and does not become lumpy. As it cools, it gets thicker.
Once it comes to room temperature, chill the mango custard in the refrigerator.
Notes
Toppings or No Toppings?
At home, we personally prefer the no topping mango custard to taste the most mango flavor.
You can add nuts and fruits of your choice right before serving, just like this fruit custard.
You can just add mango pieces as a topping to increase the mango flavor.
Do not add mango puree to the hot custard mixture otherwise, it loses its fresh mango flavor. Always cool the cooked mixture slightly and then add.Instead of custard powder, add the same amount of corn starch (corn flour) + a teaspoon of vanilla extract.Instead of cardamom powder, you can try adding some vanilla extract or sonth (dry ginger powder) like this mango jam.Instead of fresh mango pulp, you can use canned Alphonso mango pulp that is available in Indian stores. If so, reduce the amount of sugar as the canned pulp is already sweetened.