In a mixing bowl add the yogurt and whisk until smooth. To this, add the chickpea flour (besan), salt, and turmeric powder and whisk again until smooth. Add 5 cups of water and mix until well combined. Keep aside.
In a thick bottomed cooking pot, add oil, once hot add the mustard seeds. When the seeds start to splutter add the asafoetida (hing), cumin seeds, and fenugreek seeds. This is the first tempering
Once the seeds become light brown add the onions with some salt and saute until onions are translucent. Stir in the ginger-garlic and cook until raw smell disappears.
Lower the heat, give the yogurt besan mixture a quick stir, and then add it. Mix until well combined.
Increase the heat slowly to medium and let the mixture come to a boil while stirring continuously to prevent it from sticking and curdling.
Lower the heat, cover, and let it simmer for 15-20 mins.
As the Kadhi simmers, it will thicken and the color deepens. If you feel the need add more water, add ½ cup at a time. I added a total of 1 cup.
While the kadhi simmers make pakoras. The more the kadhi simmer the better it tastes. Just make sure to keep stirring in between and adjusting the water needed.