For what it's worth, I saw something very like Chris's magic oil ingredient at three takeaway kitchens I visited.
First time I was left alone in a takeaway kitchen, for a few minutes while the chef was taking an order over the phone
Curiousity got the better of me.
I opened and had a very good look in their Fridge
Kept in large empty cans from white tower puree, was old oil
Loads of it
I tasted a bit
slightly hot a bit spicy, nothing obviously that special
For ages I thought this was salvaged by simply scooped off the top curry gravy. Then I thought maybe it was just old bhajee oil.
They never told me
But when I made reference to the special oil the chef said something very odd to me
"a tiger never shows all his teeth"
still don't know what that means
But I never found out the origin of the oil.
Then one day I randomly asked for some
and I was given a litre of it.
Using this oil as an ingredient I made the best curry gravy I ever cooked
Totally authentic
And the curries I made using the gravy, were absolutely perfect.
Just like the ones that takeaway made
I knew all their recipes, but up to that point could not duplicate them
A second time I came into contact with similar oil was at a takeaway making up a big batch of gravy.
Must be 14 years ago now
They had done the boiling loads of onion bit and left the pot for half an hour
The oil rose to the top of the pan
They scooped this off into another pan
They added, garlic, tomato puree and spices
then added loads of water
They boiled it til it had reduced right down again
Maybe took 20 minutes
Meanwhile they blended the boiled onion mix
Then added the oily mixture to it
I got asked to leave after then!
Apparently I was making chef nervous
So didn't see the whole Gravy method
The third time I saw oil like this was much simpler
The chef had old bhajee/poppadom oil
He had a chip pan full of it
He heated tomato puree, garlic ginger and spices for a few minutes then simply poured this into a cooked blended Onion mix in a large saucepan.
Don't know if it was important but the onion mix had been prepared the day before
then it was boiled up again and this oil came to the top
at all the places where I used to visit, the gravy was way better than anything I could make at home
It was the whole essence of the curry made using it
so I'm really looking forward to trying Chris's recipe
Never had proper quantities before
and it will keep me pleasantly occupied for a while
I will post the results
Good or Bad
Thank you Chris