In a large wok or non-stick saucepan, heat the oil until it is smoking (NB – Do not leave hot oil unattended). Remove the pan from the heat and allow the oil to cool for ten seconds. Return the pan to the hob, turn the heat down and fry the asafoetida and mustard and nigella seeds for 30 seconds. Add the chillies, lentils and peanuts and fry for a further minute or until the lentils have started to colour.