Grind together 2 cups yogurt, dry mint powder, green chilli, salt, black salt, black pepper powder and ginger to a smooth mixture.
Add 1 1/2 cups of water and mix well. Pour the buttermilk into the large bowl. Add roasted cumin seeds powder and mix well.
Now burn the coal on the gas, it turns red properly then put the coal in a small steel bowl and put that bowl on the top of the buttermilk.
Now put 1/4 tsp ghee and add asafoetida immediately on top of the coal. once the smoke starts coming out, immediately Cover the lid. Keep it covered for about 5 minutes.So that the coal smoke and flavor mix in the buttermilk.
After 5 minutes remove the small bowl and give a quick stir. Now ready for serve it.
Serve it chilled in a glass.
