Heat 4 or 5 tablespoon of oil in a pan. Fry the cut potatoes with ½ tsp of turmeric over medium heat, let them turn golden brown in color, remove and keep aside.
Add the remaining oil in the same pan to temper the bay leaf, cardamom, peppercorn, cloves, cinnamon, and panch phoran.
Add sliced onion, fry until light golden brown in color. This step is essential to give a rich color and texture to the gravy.
Add the ginger and garlic paste, and cook until the raw smell is gone.
Add the remaining spices: salt, cumin powder, coriander powder, curry powder, chilli powder, garam masala, and tomatoes.
Cook over medium heat until the masala starts separating from the oil; this typically takes 10 minutes.
Add the chicken pieces and green chillies. Cover and cook over medium heat for 10 minutes. At this point the chicken will start releasing its juices.
Add in the fried potatoes and cook for 5 minutes on low heat.
At this point add in 2 cups of water. I prefer to use boiling hot water. Cook for 10 minutes on low heat.
You can check the spice and salt level at this time. You can add more salt or red chilli powder if you want to make the curry spicier.
Give the curry 5 minutes to rest. Garnish with chopped cilantro and serve with steamed white rice.