I reckon it's very good of this Guy to take the time and make these Video's and interesting to watch in such detail,make your own decision on His Curry's It seems he does this for a living and good luck to him

What I do like is how he makes his Base Gravy as in plenty of Oil ( Spiced/Bhaji ) and very little Water in the first stage.For some time now I have wanted to Fry the Onions etc in Oil before adding Water as we all know how much better Fried Onions taste compared to Boiled Onions

but couldn't believe BIR's would take the time to mess with Frying Onions etc but rather just chuck it all in and Boil it up and this is what
appears to be happening in most of the Video's of BIR kitchens that I have watched.
Now Julian uses 500ml of 'Spiced Oil' and just a Cup of water in the first stage of cooking so in effect these Onions are slow frying which for me is just what could really bring out that BIR Savoury taste,gotta give this a go
