Mix the curd with spices and marinate the pineapple. Keep it in the fridge for 4 hours/overnight.
Heat a pan with heavy bottom and add 2-3 tablespoon oil.
Add the whole spices with cumin seeds.
Add Onion with ginger,garlic and chillies with little salt,let it cook on medium flame until golden brown.
Add the pineapple pieces with the curd mix.Cook for 10 mins.
Add the chopped coriander and mint with remaining spice powders and salt.
Add half of coconut milk and let it cook.
Meanwhile, heat a pot with good 5-6 cups of water and salt.
Once its is boiling,add rice and let it cook for 7-8 minutes(or until its around 70% cooked).
Once the pineapple is partially cooked(70%), start taking out the rice and stack it in the biryani pan.
Spread the ghee and saffron milk using a spoon on top of the rice.
Add remaining coconut milk on top of rice,this will help pineapple to be more moist.
Cover the biryani pan/pot with a lid and add some heavy item(like 1kg flour/pressure cooker etc) on the lid.This will help you give the dum.
Let it cook on the lowest flame for 5 mins and then move the pan to cook at different places for 5 minutes at least 2-3 times i.e cook for 15-20 minutes at lowest flames, changing the position every 5 minutes.
Turn off the heat, let the pan be covered for 15 minutes.
Remove the lid and slowly mix the rice and pineapple pieces,serve warm..