When Chhena is slightly warm and cool enough to handle, transfer it to a big plate.
Crumble the Chhena with your hand, and start kneading it with your palm.
Continue pressing and kneading the Chhena for about 5 minutes until it becomes smooth and soft. Do not over knead the Chhena; otherwise, the fat will start to release.
Then add powdered sugar, and mix well using a spoon. The mixture will become very soft. At this point, taste the mixture and add more sugar if you need to.
In a non-stick pan, heat the Chhena mixture on low heat. Continue stirring the mixture while cooking; also, make sure to cook it on low heat all the time.
Cook the mixture for 4-5 minutes. The Chhena mixture will become thick again and will leave the sides of the pan.
It is essential not to overcook the mixture. If we overcook more than 5-6 minutes, Chhena will become grainy again.
To check if it is done, take a pinch of the mixture, and make a ball. It is done if you can form a ball and the mixture does not stick to your palm.
Turn off the heat and transfer the mixture to the plate. Allow it to cool completely.
Add cardamom powder, and mix well.
Shape the mixture into small balls, roll it between your palm, and flatten it slightly. I was able to make 15 Sandesh pieces from the mixture.
Decorate Sandesh with chopped nuts or saffron.
I mixed a few saffron strands into a few drops of water. Then using my fingertip, I decorated Sandesh with this saffron mixture.
Refrigerate Sandesh until the time of serving.
Sandesh stays in the fridge for up to four days.