Grease a flat tray or a rolling board with a little ghee and keep it aside.
In a heavy-bottomed pan, add 250 grams of grated jaggery and 1/4 cup of water. Heat it over a low flame until the jaggery melts completely.
Increase the heat to medium and continue cooking the jaggery syrup until it reaches a hard ball consistency. To test, drop a small amount of syrup into a bowl of cold water; it should form a hard ball.
Once the jaggery syrup is ready, add 1/2 teaspoon of cardamom powder and 1 tablespoon of ghee. Mix well.
Quickly add 150 grams of roughly chopped pistachios to the jaggery syrup and mix everything together ensuring the pistachios are well coated with the syrup.
Immediately pour the mixture onto the greased tray or rolling board and spread it evenly with a greased rolling pin to your desired thickness.
While still warm, cut the spread-out mixture into desired shapes using a sharp knife.
Allow the Pista Chikki to cool completely before removing the pieces from the tray.
Store the Pista Chikki in an airtight container to maintain its crunchiness.