Rinse the dahl well then combine with the water in a large saucepan and bring to the boil. Cook over medium heat for 30 minutes, skimming any foam that rises to the surface, or until very tender.Meanwhile, heat the ghee in a small frying pan over medium, add the mustard seeds, fenugreek seeds and dried chillies and cook, for 2-3 minutes or until mustard seeds start to pop. Add the peanuts , paprika, turmeric, cumin, coriander, asafetida and curry leaves and cook, stirring, for 1-2 minutes or until the mixture is fragrant. Add to the undrained dahl in the saucepan with the tamarind, tomatoes and jaggery and bring to a simmer. Cook, stirring often, over medium low heat for 15 minutes for flavours to develop and the liquid to reduce a little (mixture will not be thick however. If you would like it thicker, simply simmer it for longer). Stir in the lime juice, adding more to taste, season to taste with salt and pepper then serve scattered with coriander and with roti, for dipping.Notes• Toor dahl is available from Indian food stores.• Asafetida (also called asafoetida) is available from Indian food stores or Herbies spices• Tamarind puree is best prepared from tamarind pulp: chop 50 g tamarind, combine with 100 ml water in small saucepan and place over medium heat, using a potato masher to break down pulp. Strain, discard seeds and fibre, use pulp. Photography by Alan Benson. Styling by Sarah O'Brien.