Because Gagomes/Gongalo has posted this this enquiry twice, for what ever reason
I'll just paste my answer from his first thread.
Hi Gagomes, back to basics...
As a general rule of thumb, a Bengali BIR "Mix Powder" starts off with 4 main
ground spices which are the primary elements.
1. Madras Curry Powder (A historic blend of at least 12 spices)
2. Turmeric Powder
3. Coriander Powder
4. Cumin Powder
Then each Chef/Restaurant usually might add secondary spices into the Mix
5. Paprika Powder
6. Garam Masala Powder
etc...etc..
If you made a Mix Powder with only the primary spices, that would work fine.
The most successful Restaurant I'm involved with (20k+) simply uses the primary 4 + GM
cheers Chewy