Wash the daal until the water runs clear, then place it in a large saucepan with 1 litre of water. Bring to the boil, immediately reduce to a simmer and remove the foam with a slotted spoon.
Add the fresh tomatoes, green chillies, jaggery and TRS turmeric powder. Place a lid on the pan and simmer on a low heat for 50 minutes or until the daal is soft and tender.
In a pan set on a medium heat, warm the TRS coconut oil, then add the TRS dry red chillies, TRS cumin seeds, TRS brown mustard seeds, asafoetida and TRS curry leaves. Fry for 1 minute until fragrant.
Add the garlic and ginger and cook for a further 1 minute. Then add the red onion and cook until the onion is golden-brown.
Remove from the heat and add to the daal, along with the soaked fenugreek and sea salt to taste. Stir well, place the lid on the pan and simmer for 10 minutes.
Remove the lid, add the tamarind pulp and simmer without the lid on for 5 minutes.
Remove from the heat, add the chopped coriander and serve with dosa.