Wash and soak chickpeas in 3 cups of water overnight or at least for 4+ hours.
Set the Instant Pot on sauté mode and let it heat.
Add oil along with the whole spices (cumin, bay leaves, black peppercorn, and cinnamon). Saute for 30 seconds until they release their aroma.
Now add the onions, garlic, ginger and sauté them for about 3 minutes.
When the onions turn golden brown, add the tomatoes along with the spices except for the dry mango powder (amchur powder). Saute for couple of minutes.
Drain the soaked chickpeas and add it to the Instant Pot. Add the required water for cooking and give it a stir.
Switch the Instant Pot to manual or pressure cook mode for 35 minutes with the vent in sealing position.
When the instant pot beeps, let the pressure release naturally. If the pin does not drop in 20 minutes, you can release the pressure and open the instant pot.
If you like a thicker gravy, use a hand masher or the back of your ladle to mash the chickpeas a bit.
Add the chopped spinach along with the dry mango powder to the chickpea curry and stir well. Change the instant pot setting to sauté mode and let it boil for 2-3 minutes.
Chickpea Spinach Curry is ready to be served with hot parathas, naan, roti or a steaming bowl of rice.