take 3 medium-sized onions. cut them into very thin long slices.
deep fry onions until they turn into a nice golden brown color.
add 4-5 tbsp of oil(you can use the leftover oil used for deep-frying onion and mix again.
put the fish pieces and mix gently.
add whole garam Masala spices, salt, and a little oil.
bring the water to boil. when the water starts to boil add the soaked Basmati rice.
water stops to boil after adding the rice, so bring it to boil again.
cover the pot with aluminum foil and cover with lid.
turn off the heat. transfer the biryani into serving bowl turning the pot upside down.