Pressure cook both the dals in 2 cups water for 4-5 whistles. Add salt and whisk well. Keep aside.
Heat 2 tbsp. oil in a pan and temper with 1/2 tsp. cumin seeds, 1/2 tsp. mustard seeds, red chilly and urad dal. After it stops spluttering add the asafoetida, onion, ginger, garlic and curry leaves.
Saute till light brown. Now add the cumin powder, red chili powder, turmeric powder and garam masala powder. Sprinkle a little water and saute for a few seconds.
Add the tomatoes and continue to fry till oil leaves the sides of the pan. Now add the boiled dal, salt and split green chilies.
Simmer on low flame for 3-4 minutes. Remove from the flame, add the lime juice and keep aside.
Heat remaining 1 tbsp. oil and temper with the remaining mustard seeds and cumin seeds. After it stops spluttering, switch off the flame and pour this tempering on the prepared dal. Serve, garnished with coriander leaves.
