Put the moong dal in a medium pan and add 800ml of water. Bring to the boil. Skim off the white froth and add the turmeric. Stir to mix. Cover partially, reduce the heat to a gentle simmer and cook for 45 minutes. Add salt to taste and stir to mix. Turn off the heat.

Pour the oil into a small frying-pan and set over a medium-high heat. When hot, quickly add the asafoetida, cumin seeds and chillies in that order. As soon as the chillies darken, a matter of seconds, put in the shallot. Stir and cook until it browns, then quickly pour the contents of the frying-pan over the cooked dal. Stir to mix.