Add dal to a pressure cooker and wash it few times. Drain off the water.
Pour 2 ½ cups of fresh water to the pressure cooker.
Sprinkle 1 teaspoon salt over the green mango. Scrub it very well and rinse off. Chop it to pieces, discard the seed/kernel/stone. You don't need to peel the mango as the actual flavor comes from the mango skin.
Add the mango pieces to the cooker along with turmeric & 2 green chilies (reserve the rest for later).
Pressure cook for 2 to 4 whistles if cooking directly in the cooker. or 3 whistles if cooking in a bowl placed inside the cooker.
When the pressure drops, open the lid. Mango dal must be soft cooked.
Add salt and mash lightly. If the consistency is too thick you may pour half cup boiling water and mix to bring to consistency you like. Taste test and adjust the salt.
Heat ghee or oil in a small tadka pan. Reduce the heat and add mustard, cumin, dried chilies, garlic, ginger and green chilies (optional, use for more heat).
When the ginger turns aromatic, add curry leaves, hing and more turmeric (if required for color). [If you like chunky pieces of mango in your dal, add ⅓ cup bite sized mango pieces to the tempering and pour few tablespoons of water. Cook until soft.]
Pour this tempering to the mamidikaya pappu and stir well. Keep it covered for a while so the flavors are infused.
Serve mango dal with rice or chapathi.
Press saute button and pour oil to the steel insert. Once hot, add mustard, cumin, 2 green chilies, chopped ginger, garlic and curry leaves.
When the ginger becomes aromatic, press cancel. Add hing, turmeric, dal, mangoes and 3 cups water. Mix well.
You can also place your rice bowl over a trivet. Secure the IP with the lid and position the steam release vent to sealing.
Pressure cook for 11 minutes. When the pressure drops open the lid and add salt. Mix well and pour ¼ cup boiling hot water if required to adjust the consistency.
If your dal is not spicy enough, you may fry fine chopped green chilies in 1 teaspoon ghee and add it to the mamidikaya pappu.