In a medium bowl, wash the dal (lentils) thoroughly twice and soak it in water for 15 minutes (this will tenderize the dal and will cook faster).
Transfer the contents of the bowl to a pressure cooker/ instapot and add sufficient water for cooking. Give it 3 whistles on medium flame. Let it cool. Once cooled mash the dal into a fine paste and keep it aside. If using Instapot: 1:3 lentil: water ratio, 7 minutes high pressure, 15 minutes NPR.
In a medium cooking pot, heat oil and add curry leaves, dried red chili, mustard, cumin and fenugreek seeds. Let it cook for a minute.
Now add red chili powder, turmeric powder and ginger garlic paste. Cook for another minute.
Next add drumsticks, bottle gourd, baby red onions (or diced red onions). Cook for a minute and then add sufficient water to cover the vegetables. (This step is optional as adding vegetables is your choice).
Once the water evaporates, and the veggies are cooked, add the tomato paste (or chopped tomatoes). Cook for another 7-8 minutes. If using the paste, add water to dissolve it.
Next add the tamarind pulp/ paste and cook for another 7-8 minutes. Add water if necessary and bring the contents to a boil.
To the boiling mixture add the dal paste and add sufficient water to get a running consistency.
Add salt and green chilis and bring it to a boil. Let it boil for 10-15 minutes.
Remove the pot from heat and transfer dal to a serving dish. Garnish with cilantro.