To begin, in a large bowl, marinate the chicken with salt, Kashmiri red chilli powder, turmeric powder (haldi), and the juice of one lemon. Mix well and keep aside.
Heat mustard oil in a pan to a smoking point and let it cool a bit. Flash fry the chicken pieces in batches on high heat until they colorize. Remove and keep aside.
In the same oil, add in bay leaves and whole red chillies.
Next, add in cumin seeds (jeera) along with whole garam masala. Allow them to crackle.
Now add in sliced onions and saute until translucent.
Add in finely chopped ginger and garlic, and whole garlic knobs. Saute until the onions begin to change color. Do not brown.
Reduce the heat. Add in the dry masalas - salt, Kashmiri red chilli powder, turmeric powder (haldi), cumin powder (jeera), and coriander powder (dhania). Mix well. Add some water so that the masalas do not burn.
Cover with a lid and cook for a few minutes until the oil starts appearing on the sides.
Now add in the fried chicken pieces. Mix until well-coated. Add water, cover a lid, and let it simmer on low heat for 10-15 minutes until the chicken pieces are cooked.
Finish with garam masala powder and mix well. Check the salt and add more if required. Adjust the gravy as per your taste.
The Bihari Style Chicken Curry is ready to serve. Enjoy with litti or boiled rice.