Heat a pan, add ghee and roast the cashews in medium flame. Once golden and crisp, drain from ghee and set aside.
In the same ghee, add rava.
Fry in medium flame, with constant stirring until a nice aroma comes (the rava will start turning golden brown here and there).
Transfer the mixture to a plate and set aside.
Add water to the pan and bring to boil. Add the fried rava little by little to the boiling water and keep stirring simultaneously.
Eventually, you can also side by side boil measured water needed for the recipe and add it to the roasted rava saving the transfer.
Take care no lumps are formed, keep in medium flame and stir well.
Keep in low flame and cook covered for 4 minutes or until the rava gets cooked well.
Add sugar, kesari colour (please use natural food colour) and keep the flame in medium and stir well.
Some times, when you add sugar and mix, immediately you may find very few lumps or tiny lumps, but don't panic, stir well in a way to mash those lumps, it gets mashed well in the heat.
Stir in medium flame for 4 minutes or still the kesari forms as a whole mass (doesn't stick to the pan at all).
Add ghee fried cashews, cardamom powder to this if desired.
Optional : Grease a plate with ghee and spread the kesari in it and after cooling down, cut out as diamonds with a knife.