Heat a thick bottomed heavy kadai or pan. add 1 cup peanuts in it.
On a low to medium-low flame, roast the peanuts stirring often till they become crunchy.
Grease the back of tray or plate or a marble board with some ghee or oil.
In a kadai or pan, take jaggery powder. you can also use jaggery block. if there are impurities, then you will need to strain the jaggery syup. Add water.
Heat the kadai or pan on a low flame. with a spatula or spoon, begin to stir, so that all the jaggery gets dissolved.
keep on stirring the mixture often.
Cook the jaggery syrup on a low flame with frequent stirrings.
While the jaggery syrup is cooking, also keep a bowl of cold water where you can check the consistency of the syrup.
keep on cooking till the mixture reaches the hard ball stage.
Check the syrup in cold water and it should be firm, brittle and break or snap easily.
When the jaggery comes to this consistency, quickly add the peanuts and give a quick stir and mix very well.
Switch off the flame and quickly pour the chikki mixture on the greased plate or marble board.
Quickly place a foil or a butter paper or parchment paper on the chikki.
With a rolling pin (belan) roll to even out the chikki layer.
Next remove the paper and then with a knife, cut horizontally and vertically. let the peanut chikki cool at room temperature.
Once cooled, break them and serve peanut chikki. if not serving, then store them in an airtight jar at room temperature.