i have tried most top brands of spices. to be honest you are better off just making your own spice mixes from scratch . i spent a year doing as many traditional indian recipes as possible. this teaches you about spices. i now use this knowledge in bir style cooking.
    A typical rahjer madras powder will contain coriander, cumin, tumeric, fennel, mustard, poppy seeds, clove, cinemon, methis or fenuggreek, maybe nutmeg. Learning how to use these powerful spices is much better than just using a tsp of ready made rahjver madras powder.
   By learning how the spices work together you can make much tastier curries. For example its essential to understand how coriander and cumin work together. some curries require a ratio of 2 parts cumin to one coriander. other recipes require a ratio of 1 part cumin and 2 parts coriander. and some require equal amounts of each. This type of knowledge is how i went from novice to spice master. my curries improved 10 fold in a 2 year period by learning this. I apply this to bir cooking each week , using base, and my own spice mixes. If you must use commercial spices then rahjver are good, but dont give the bir taste all on their own. That taste comes from much much more. 

yes , the bir chef i know, does a lot more evaporation for bhuna, and adds more onion. he also adds more tumeric. the end result is dry, and not as saucy as madras. he even used 2 pans for the single dish he made me during my demo. half the sauce in one pan, the rest in another. this improves the taste he said.

MINT MINT MINT,  ;D  i dont think we use enough, and its quite noticable in several good bir ta's i frequent. its for balti especially. I suspect they use dry mint leaves, if you are wondering.

Hi 976bar, i am not sure about base keeping me alive lol ! but making it all the time is killing me !  ;D

Thanks mate.  i guess cabbage is quite watery ,so should help produce a thin watery base, which is good for high temperature reduction/evaportaion. all my best bases have been thin and watery.  the real bir base i tried was quite greenish brown. maybe its similar to your attempt.

i agree panpot, its up their with my all time favourites. i use lamb in this dish, and not chicken, and add a tbs of the lamb stock. this tastes like a real bir ta once the stock is added.

hi , for a standard base with 3 or 4 pints water and between 1 and 2 kg of onion, how much cabbage would be the right amount? i guess about a quarter of a white cabbage? does that sound right?

tried this recipe and i give it 8 out of 10. it was very flavoursome, in a pataks type of style. not quite like the pre cooked chicken from my local which is very lightly spiced compared to this recipe. However i was pleased to try the recipe and may use it again. so thanks to whoever posted it. nice one

Having hit a point with curry making where i cannot seem to improve, i thought i would re visit the kd secret onion paste and also make some onion oil. They were both a complete waste of time, and made no significant difference. in fact i cannot remember such a huge disapointment  :-X  the kd secret onion paste is a joke. and making onion oil sounds good in theory , but fails miserably. 

Just brought the rajher hot curry paste, as i like their powders. Its a big improvement on pataks. almost no gritty bits, and much milder bir taste. I added a tbs of spice mix and garlic and base to the paste (with a few other typical ingredients) and for a quick mid week curry it was good. If you like ashoka curry, then i would recomend this paste. Its a real step up from pataks. although i do prefer to make my own spice mixes most of the time.