In a medium size bowl add in the Besan and yogurt and make a smooth paste.
Slowly add water to the mix and keep on mixing to make it lump free and smooth consistency.
One can either make buttermilk before and add to the besan mix. Either way is fine.
Now in a heavy bottom pot add the Oil.
Once hot, add in the mustard seeds, and curry leaves.
Let the mustard seeds crackle.
Now add in the grated ginger, grated garlic, green chilli and saute for 1-2 minutes on medium.
If using fresh turmeric add it in the previous step.
Now add the yogurt besan / buttermilk mixture and let the mixture come to a boil on medium.
Keep on stirring in between,else the besan will stick to the bottom of the pan.
Once you get a boil add in the turmeric powder and salt and let this cook on slow for at least 10 minutes.
This will cook the besan/ gram flour thoroughly.
Once done, switch off.
Enjoy it hot with a garnish of coriander.