MarkJ - I am so grateful to you for posting the "30-35 onions" base sauce recipe. Last night, I scaled it down roughly pro-rata to 2 onions, adapted it marginally, and ended up with by far and away the best base sauce I've ever made! I've no doubt other base sauces listed here at this forum are good. It just happens that this is the first one I've tried, and I'm very pleased I did.
I encourage others to try Mark's recipe. Don't be put off by thinking you need to make the 30-35 onions version. I'm not saying it won't be even better, but I somehow doubt it. The previous versions of base sauce which I have tried over many years came from 'The Curry Secret', curryhouse.co.uk and, of course, Pat Chapman. All required a lot more effort than the MarkJ recipe, and none came remotely close in terms of flavour at the end. I am very optimistic that this base sauce will allow me to produce a good BIR chicken korma and various other dishes.
The colour is yellow, definitely not red, despite 2 tsps tomato puree being added.
As I said, this base sauce tastes excellent but, in a way, that's irrelevant, if promising. It will only be proven when I use it to make a final dish.
Regards
George