Hi Haldi,as when I started this thread I have found it's the aromatic spices as used in garam masala that gives me that lovely savoury flavour I have been missing in my home cooked curry's, also having spoken to the boss of the t/a I believe no additional spices are added to the final curry such as coriander and cumin as they are allready in the garam masala and I also believe there is no turmeric or paprika added as this is in the base gravy.
I also asked if they use any g/m in their base gravy and he said yes,I then asked about white cabbage in the gravy and he said no and continued saying 'you could put anything in the gravy and it wont taste much different than if you only used onions unless you put a lot of a particular item'.
Then thinking back to the time I spent in a BIR kitchen and ' the chef's own masala' as It was called and the colour and texture (light brownish and coarse) with no obvious turmeric added it all seems to be making sense now