Wash the basmati rice and soak it for 30 minutes.
Grind ginger , garlic , green chili and mint leaves with little water.
Slice onion and tomato.
Fish Marination :
Slice the fish into medium pieces. Clean and wash the fish pieces thoroughly.
Drain water completely and add the pieces to bowl.
Add turmeric , chili powder , salt , lemon juice and oil.
Marinate and let it rest for 30 min.
Heat a heavy bottom pan over medium heat.
Add oil and ghee. Add in the whole spices (bay leaf , cinnamon , cardamon , cloves and star anise)
Saute once and add sliced onions.
Saute often until onion starts turning brown.
Add the paste (ginger garlic mint chili). Saute until there is no raw smell of ginger garlic.
Now, add sliced tomatoes and cover with a lid. Allow it to cook until soft and mushy.
Add beaten yogurt(curd) and cook for few min.
Add in turmeric , chili powder , garam masala and salt. Saute for 4 min.
Spread the base masala evenly on the pan. Do not combine the base after this step.
Arrange the marinated fish. Evenly spread the soaked rice over the fish.
Now add 1.5 cups of water.(Add more or less water as needed. Generally we need 2 cups of water to cook 1 cup rice. We already have some moist in base masala and fish pieces will leave some water when cooking. So 1.5 cups of water should work perfect)
Check for salt and cover the pan with a lid. (You can use chapati dough to seal the lid)
Let it cook over medium heat for 7-10 min until rice gets half cooked. (Do not open the cover often. I opened it just to show how it should look)
During this time, heat a tawa / pan(for Dum)
Place the biryani pan over the hot tawa and allow it to sit for 15 min over low heat.
After 15 min turn off the heat and add coriander and curry leaves.
Cover and leave it for another 15-20 min. Then gently combine the biryani without breaking the fish pieces.
Chop fish into medium size pieces else they will break easily while cooking.
Use a pan with wide bottom so that all your fish pieces are able be sit in a single layer.
If you do not have a tawa for making Dum, just cook it for 10 min over low heat and let it rest for 15-20 min after turning off the heat.