Cook the tur dal separately, mash and keep it ready.
cook the tomatoes and green chillies with little water. mash and keep it ready.
heat oil and crackle mustard seeds, cumin seeds, curry leaves.
fry small onions until reddish and then add cooked tomatoes, cooked dal
grind together garlic, coriander powder and chilli powder to a fine paste. add the paste to the curry.
furthermore, add asafoetida, turmeric powder, salt, water and mix well.
give it a boil and serve hot.