Welcome to the site! There's loads of info on here, including a variety of curry base gravies, mix powders and just about anything you can think of that's curry-related.
I used to frequent Gibson Street myself, although it was in the 70's!
I suspect your Lamb Kasoori had an overload of Kasoori Methi, or dried fenugreek leaves as its otherwise known. If that's not right, someone who knows better will be along in a mo to give a better suggestion.
If you pop down to one of the Asian food stores, such as KRK and others, in Woodlands Road, you'll pick up a pack no bother. Maybe there are good Asian grocers nearer you over in Pollockshields that would do as well.
A quick Google search will land you on a few Lamb Kasoori recipes, although they tend towards the traditional cooking methods rather than the BIR (British Indian Restaurant) style that we favour on this forum.
That's not so say that traditional cooking is bad - quite the reverse! But we tend towards "assembling" meals using pre-prepared ingredients. So, you might start off by frying off garlic and ginger paste in oil, adding a sort of curry powder known here as mix powder because it contains many spices, one of which might actually be curry powder! You might even add a dod of Kasoori Methi at this stage! Then you might add blended tomatoes or tomato paste diluted with water to prevent the spices burning, followed by a pre-prepared base gravy and meat and/or veg. That would give you a basic curry in about 10 minutes using pre-prepared components rather than slaving over a hot hob for hours!
Have a look around the site and you'll soon get the idea. You'll also get a sense of those who can be relied upon to know what they're talking about - I don't include myself in that category BTW!

Happy currying!
