Wash and soak the dal in water for five minutes.
Transfer the dal into a pressure cooker and add water until the dal is fully immersed.
Cook for 3 to 4 whistles or until the dal becomes soft and mushy.
Mash the dal using the back of a spoon and keep aside.
Heat a pan with oil, add mustard and Urad Dal. when they crackle add curry leaves along with the slit green chilies.
Next add the chopped tomatoes along with turmeric powder and stir everything well. Cover and cook until the tomatoes are mushy.
Add the chopped spinach and sauté for 2 minutes then cover and cook for 5 minutes.
Then add the mashed dal and mix well with the spinach. Add ½- 1cup of water and season it with required salt.
Note: Adjust water according to the consistency you want the dal
Finally, add the cumin powder and mix well. Cook on low flame for 5 minutes.
Transfer the dal into a serving bowl and serve hot with your favourite roti or steamed rice.