How to cook biryani?

To be honest there are 100s of ways to cook this dish and I must say no one can claim his method or recipe is the best. I would say which ever methods you choose the following must be present;

a) fundamental ingredients like yogourt, major spices and basmati rice,

b) fundamental technique

I started cooking biryani in 1990 and has been cooking since. I know a few major methods but I must tell whichever methods you choose, sheer persistence and practise are paramount.

I have very limited space in my kitchen so I am not able to cook in large quantity. Biryani tastes and cooks better with large quantity. If you live in an apartment, you would be lucky if you can cook for say 50-100 people. I have managed to cook for 50++ so far, but it was rather messy.

The picture should my magic biryani pot. That pot has churned out tonnes of steaming hot and pluffy briyani.