Wash the potatoes and boil till they are just done , add 1 tsp salt in the boiling water.(dont over cook )
If you don't have baby potatoes then boil normal potatoes and then cut into big pieces.
After boiling peel the potatoes and cut into 2 pieces, sprinkle some salt over them and mix (adding salt in steps helps absorption of salt inside the potatoes and they will not taste blend)
(I prefer to chill potatoes in the refrigerator for some time so they will not break while roasting )
Heat few tbsp of oil in a wide heavy bottom pan and add the potatoes pieces and let them roast for few minutes so they get a nice colour and crust.
If you are in hurry then can skip this step or just deep fry them quickly.
Take curd in a bowl and whisk well and then add gram flour and all the dry spices in it except salt and garam masala.
heat 3 tbsp of oil in a cooking pan and add cumin seeds, when they start to crackle then add cardamom, bay leaves , whole dried red chili and asafoetida
Once the tempering is done , lower the heat and add the curd mixture in the pan and keep stirring till it start boiling, keep cooking till it become thick and start releasing the oil.
Add the potato pieces and salt ,mix well. Now add 1.5 cup hot water in the curry and stir to mix.
Cook it till it start to boil again, keep stirring till then.
Now add sliced green chilies and cover with a lid and simmer for 2 minutes.
Add garam masala and chopped fresh coriander and switch off the heat and let it rest for 5 minutes.
The gravy will thicken slightly when it cool down .
(You can adjust the quantity of water in the curry as per your preference )
Enjoy dahi aloo sabji with paratha, poori or bedmi !