Wash and soak the dal for 15 minutes in water. Strain any excess water and keep aside until use.
Heat a pressure cooker with a tsp of oil, add green chilies, chopped tomatoes. Dump the strained dal, add turmeric, salt and coconut.
Add 3 cups of water to this dal mixture and pressure cook for 4-5 whistles. Let the pressure fall naturally. Then open the cooker and give the dal a good mix.
Let us add the tadka, heat a small tadka pan with oil, splutter mustard seeds, add broken red chilies, curry leaves. Add chopped garlic and ginger to this and let the garlic brown well. finally add cumin to the hot tadka, give it a stir.
Pour this sizzling tadka over the dal and garnish with fresh coriander leaves. Serve the dal with steaming hot rice.