Pressure cook dal with a pinch of turmeric powder for 3 whistles. Mash well and keep aside. Chop spinach finely. Chop onions, tomato, ginger, garlic and chillies finely. Pressure cook spinach for 1 whistle. After the pressure subsides, open and mash it well. Heat oil in a pan or kadai, add the oil, mustard, jeera seeds, red chilli and a pinch of hing in the same order and fry till urad dal turns golden brown.
Add onions, ginger, green chilli and sauté till onions become light brown. Add finely chopped tomatoes, turmeric powder, chilli powder and cook till tomatoes become mushy. Add the cooked palak, cooked dal, salt to taste, mix well and bring everything to boil. Remove from fire and add a tsp of ghee.