In a plate/bowl put all the ingredients of marination and mix it well now put properly washed pompheret pieces(u can use surmai fish or prawans).keep aside for 10 mins.
Take all the ingredients of masala and and add little water and make paste keep aside.
Heat 1/3 cup of oil in a pan and slightly fry the fish pieces(fry for 2mins only).remove and keep aside.also keep the remaining oil aside we will use this in masala.
Take potato pieces and fry them in oil on low flame untill golden and keep aside.
Now take kadhai and put remaining fish fry oil and add 2 tbsp more oil.then add remaining marination masala and 1/3 cup of fried onion(birista) and mix it after that add grinded paste and saute for 2 to 3 mins.now add chopped tomato and little water and saute for 5 mins.
Now add red chilli powder+salt+coriander powder+cumin powder+garam masala powder+turmeric powder and mix it well saute for 2 mins.now add whisked dahi and mix it well cook for some mins then add 1/3 cup water and fish pieces very carefully place in masala and leave for 1 min (donot stir it).then remove fish very gently and keep aside.
Add fried potato pieces and cook masala untill water dries and masala gets nice and thick.
Now heat water and put bay leaves +cinnamon stick+ elaichi + salt + lemon juice and cook rice on high flame(cook rice 80 %).discard all the remaining water.
Now take dekchi put cooked masala on that sprinkle chopped coriander leaves (1/4 cup) + mint leaves(1/4 cup) + fried onions(1/3 cup).and put all the rice on top of rice put yellow or red food colour mixed with little water and sprinkel little mint and coriander leaves chopped and place fish pieces.
Now keep on dum for 15 to 20 mins on very low flame.
Your fish biryani is ready enjoy with khuchumber or salad or raita.
