Thats what I did last night. Made up a smaller raw batch and dry roasted it in a small pan first - just enough for 2 portions. Closest to BIR aroma and taste I have ever got to after all these years. I dont notmally post on Forums, I just lurk in the background ! However, this dry roasting of the powdered spices is a revelation for me and I just had to give feedback 

This chicken curry/thick onion puree approach has me intrigued. I think there's something good here -  I just need to play with it a bit to figure it out. I doubt he just gave up his full technique (it's his signature dish after all) but he does give (me at least) a lot to think about.

Romain
              This is a similar puree approach I now use as standard, for me it is achievable by the use of a slow cooker. Think of reverse engineering whereby your aim is to remove as much liquid as possible whilst retaining or intensifying the flavour.
  Proceed with your base to the point prior to adding any liquid, then transfer ingredients to a slow cooker, just cover with water and cook on low heat, adding more water only when and if needed, When you see the oil rise and are happy with the reduction liquidize the contents, carton up or cook further till required consistency is achieved. The only warning I will give is to carefully remove the skin which will form around the interior rim of the cooker as it reduces prior to liquidizing. It can give a burnt taste if left in.
  For me it works, I now have 12 portion's within three 300 ml containers. Instead of the usual 12 containers, great space saver, I am also able to defrost each portion quicker, whilst adding the appropriate liquid/stock to suit the dish i.e.chicken, beef, lamb vegetarian etc. Further enhancing the flavour of the dish. Like I said it works for me, try it, you might like

Regards pap rika

(thank you Glebe's  youtube channels)