I'm probably repeating what has already been said but, the smell that comes from my local takeaway is almost a barbecued aroma, suggesting that the secret is not an ingredient but the use of flash-frying to sear your final curry. All BIR's will do this but I bet not many of us do. We don't have big cookers or hoods or fire extinguishers.
Sorry to disagree with you Dirk. I'm not disputing what you're saying about the possible source of the aroma (albeit a bbq one?), but BIR's do not
all do this. My regular restaurant doesn't for sure, neither do a few other "open kitchen" takeaways I've used. The aroma is still most certainly there. In fact their burners aren't much different to the largest gas ring I have at home, which most modern hobs now have as standard.
Having said that, if I did want to flash-fry a curry at home, my largest burner ring (3 kW) would be ample, but as you rightly imply, it would make a bit of a mess, and her indoors would certainly object .... and fire extinguishers are expensive ... and if you were right, I'd have a queue outside my front door!
Regards
Sn's ;D