Boil the milk, then lower the flame and cook till the milk starts to thicken and reduce in quantity. Once the milk has reduced, pour in the vinegar and stir. The milk will form curdles, pour this curdled milk into a pan lined with a muslin cloth. Squeeze the whey out and keep the chenna aside. (Note to throw away 1 and 1/2 cup of whey while storing the rest of it).
Cook the chenna along with the rest of the whey and sooji, till the moisture is reduced. Add sugar and cook till you achieve a smooth dough like texture. Add the elaichi powder and ghee, stir it well.
Grease a plate with the ghee and pour in the kalakand mixture. Smooth it with a spatula. You may garnish it with nuts.
Let the kalakand cool down completely.
Slice the kalakand and serve it in room temperature or cold.