Add oil to a hot skillet
Add asafotida, cumin and mustard seeds.
Once the seeds pop, add chopped onion and sautee for few minutes until light brown.
Now add the green chillies, ginger and garlic. Sautee until light brown.
Add turmeric and coriander powder. Sautee for a minute until fragrant.
Add besan/ chickpea flour and cook for few minutes until its fragrant and the rawness goes.
Remove the skillet from the stove and add salt and the hot water. Continuously whisk the mixture so no lumps are formed.
Now transfer the skillet back to the stove. Let the curry bubble away on a low flame, whisking continuously until the liquid thickens and forms a glossy curry. It should neither be too thick or thin in consistency.
Enjoy with some ghee and Bajra Bhakri.