Rinse and soak the whole black urad dal for at least 6 - 8 hours or overnight. In a pressure cooker add the soaked dal along with about 3 to 3½ cups of water and salt. I also add crushed pepper and heeng to the dal and 1 tsp. mustard oil for a sharp taste. You can skip the mustard oil or use ghee in its place. Also add half chopped onion, 1 tsp. each minced ginger and garlic and 2 chopped tomatoes.
Pressure cook for 6 - 7 whistles on medium heat or until the dal is soft and mashable. Takes about 15-20 minutes. Allow the pressure to release naturally. Then open the cooker. Your dal should be cooked. Add a little water if needed and put it back on stove.
To season the dal or for its tadka, take 1 tbsp. of ghee in a pan and heat it. Add in cumin seeds and allow them to sputter. Add in ½ chopped onion and ½ tsp. Chopped garlic and let it cook for about 2 minutes or till it turns pink.
Now add in 2 tsp. Kashmiri red chilli powder, 1 tsp. Garam masala and 1 tsp. Crushed kasuri methi. Mix the tadka well and turn off the flame.
Tip in the tadka to the simmering dal. Mix well and simmer for 5 minutes more. Also using a potato masher or the back of a ladle, crush some dal. You will notice that it becomes thick and creamy. You can add some water if it gets too thick.
Taste and add more salt, if needed. Garnish with chopped cilantro and serve piping hot. You can add a small blob of butter, if you so prefer. Your kali dal is ready to serve. It is delicious.
Notes
1. Soaking the dal is important for a creamy texture and quicker cooking time.2. Use a pressure cooker or Instant pot for cooking the dal. It will take too long if you try to cook it in a pan. 3. Simmering the dal after it has cooked helps give it a creamy texture.4. Leftovers taste even better the next day. Just reheat gently with a splash of water.5. If your dal is still a bit uncooked after pressure cooking, you may pressure cook for a couple of whistles more. This time difference could be due to the quality of lentils used.