Place sago pearls in a colander and place the colander over a large bowl. Wash the sabudana under running water 1-2 times. Using your fingers, gently move around the pearls and wash thoroughly. At first you will see, very milky water collecting in the bowl, keep going, after 4-5 washes, the water will start getting clearer. This method not only cleans the sabudana but also removes excess starch coating the pearls.
Drain the water. Place sabudana in a bowl and add ½ cup of clean water. Set aside for 6-10 hours (overnight is the best). The pearls will plump up as they soak. The time of soaking depends on quality of your sabudana, it can take upto 10 hours to become soft. Make sure that after soaking, the tapioca pearls are soft and can easily be squeezed between thumb and finger. Drain the water(if any) after soaking. Set aside.
In a heavy bottomed pot, melt the ghee on low. Add the nuts to it and saute for about 20-25 seconds till you smell the aroma. Take out in a bowl and set aside.
In the same pot, add the cardamom pods and pour the milk. Set the stove on medium and let milk come to a boil. Reduce the heat to low and let the milk reduce slightly for 8-10 minutes. Stir intermittently to make sure that the milk is not sticking to the bottom.
Once the milk is reduced add the soaked sago. After adding sago make sure to stir continously for a minute so that the sabudana doesnt clump up.
Cook on low heat for next 10-15 minutes stirring intermitently till you see that sago pearls have started to become translucent and are cooked through. The kheer will be thickish and have a velvety silk like consistency. Don't make the kheer too thick because it will thicken as it cools.
When the kheer is thick enough (thicken it more than you think, since condensed milk will thin it out),mix in the condensed milk/ jaggery (image 7). Read below for jaggery instructions. Simmer for another 5 mintues if you added condensed milk. Mix in the nuts and cardampm powder.
Serve the kheer warm or cold (if desired). It will thicken quite a bit as it cool down.