Wash the dry chickpeas and soak in enough water for at least 5 to 6 hours or overnight for best results.
Once the chickpeas is soaked in water for few hours or overnight, discard the water used for soaking and rinse the chickpeas again in fresh water. Keep the soaked and washed chickpeas aside.
Peel and chop the onions finely, keep aside separately from the chickpeas.
Chop the tomatoes in small pieces, keep aside with the onions.
Thoroughly wash the potatoes and peel the skin of the potatoes, using a good quality potato peeler will make this job easy. Keep the potatoes aside separately from the tomatoes and onions.
Heat 2 tablespoons of oil in pressure cooker, add the mustard seeds.
When the mustard seeds splutter, add the broken dry red chilies and fresh curry leaves, fry for a few seconds.
Add the chopped onions and tomatoes, saute for about 2 minutes.
Add the potatoes and chickpeas, mix everything well.
Add the salt, ginger and garlic, stir well and saute for another 2 to 3 minutes.
Add all the remaining spices to the pressure cooker, mix well and saute for another 1 more minute.
Add the water and mix well, close the pressure cooker with the lid and safety valve and cook for about 5 to 6 whistles or for about 12 to 14 minutes in medium heat so the chickpeas will get completely cooked and soft.
After 12 to 14 minutes of cooking, switch off the pressure cooker and wait for the pressure cooker to cool down.
Once the pressure cooker is cooled down, open the cooker and see if the chickpeas is cooked enough and soft.
Mix well the contents and you may heat the contents in medium heat for another 2 more minutes which will really help with thickening the gravy more. If you think gravy is less, you may add a bit more water and heat for a minute.
Add the extra one tablespoon of oil to the pressure cooker and mix everything well.
Keep the pressure cooker closed for few minutes or until serving, which will make the gravy more thick and delicious!
Serve the hot potato chickpea curry with rice, puttu, chapathi, dosa or any bread or dish you wish to serve it with!