Sorry to have to say that you wont find this very helpful. The usual story - reluctance on the part of chefs to 'tell it like it is.'

  UPDATE.

         Shah Zahan appears to have joined the rest and jumped on the 'Blandwagon.' After around fifteen years of fantastic currys this is a real loss.
                                D.

    Some trad. Indian dishes do use onion that has been ground by mortar and pestle along with garlic and ginger. Modern version of course uses blender or food processor. Loads of oil needed to cook of course, and flavours can be similar to BIR.

    You have stumbled onto something really important here. The flavours of some vegetables - garlic is probably the best example - survive cooking much better if they are pureed first. For this reason, when making curry gravy, you must always add garlic as a puree, or for smaller amounts, blend it with some of the water. Of course, the opposite is wanted with onions. If pureed before cooking, the resulting flavour may be perfectly acceptable, but it won't be BIR.

                     Dave.

The Good Food Takeaway is in Unthank Road.[It used to be the Halal Meat Co.{!}]

I agree that Shah Zahan, Waterloo Road, when on form [which is almost always] is unbeatable for standard curries. [ Vindaloo, Jhal Frezi, etc.] Most veg side dishes excellent, too, but I wouldn't bother with their tandoori. Their dishes have changed very little since they opened around 1990.
    Incidentally, this one, unlike the Good Food, produces the smell / flavour in abundance!

                                            D.

  It is unlikely that any curry is too hot for a true chilli head, who enjoys the taste of chilli and dosen't really notice heat. But the important point is, TAKE NOTE, most 'hot' currys are not worth eating, and many are just plain INEDIBLE. Please reflect on this.

                                              Dave.

  An interesting one, this. Dosen't appear to be Bangladeshi run. Dishes don't  have the flavour / smell, but are excellent quality restaurant currys of heroic proportions. My chicken phall fills a 500 ml. container. Extra portion of phall sauce fills another 500 ml. container. My wife's lamb chilli masala or jeera lamb fills another. Pilau rice fills a standard [350 ml.] container. All this, plus 2 keema nan and 1 plain nan, ?15.40 delivered.

    Here's an idea that may be worth kicking around - when a large pot of sauce is heated, it takes longer to reach boiling point than a smaller one, and also longer to cool down, so the cooking time is effectively increased. Some ingredients will lose flavour, some may actually end up over cooked. The level of salting will remain the same, but overall the sauce could end up tasting saltier because of the loss of flavour of some of the other ingredients. These effects could be the source of some of the rather unscientific theories that occasionally turn up. Just a thought.

    Drawback is they're a bit on the small side, so food is a bit close to the heat , which results in uneven cooking, especially of nan. Also, you must regard these as suitable for outdoor use only, unless you install an industrial-grade extraction system. A better investment would probably be a BBQ grill for meat, and try your hand at the tava method for nan. [With practice you really can make restaurant grade nan and k.nan.

I agree re. spiced oil -  it is a by product of the whole process, but does have uses, rather than something that is deliberately produced. It might as well be referred to as waste oil. Another factor is that some local councils operate a collection and disposal service for used cooking oil.[Which they of course charge for] If a fast food outlet dosent make use of this 'service', it may be assumed that they are disposing of their oil illegally, ie, down the sink. So some oil has to be saved, just so that they can pay to have it taken away!