In a thick bottomed pan, add sugar and water and bring to boil.
Reduce flame when boiling starts. Boil for 4-5 minutes.
Add cashew nut powder. Mix well to make sure that no lumps are formed.
When everything is mixed well, add 1 tsp ghee (if adding).
Keep stirring continually. When mixture starts to thicken, switch off.
Keep stirring till the mixture turns in to a thick dough ball, as it cools.
When the dough is thick enough to roll, place it on the greased sheet which you have kept ready.
Use a rolling pin (belan/Latne) to roll the cashew ball as thick or thin as you want. Generally kaju katli is thin, about 1/4 cm thick.
You may place dough in between two sheets to roll if you wish.
As soon as rolling is done, cut in diamond shapes using a knife. If you are using the silver foil, apply it before cutting.
Let cool completely. No need to put in the fridge.
Keep the diamond shaped kaju katli in airtight box and use when required. It will keep good up to 2 week at least (usually it gets eaten even before that).