When I went to make this much loved recipe, I discovered that I had a couple of issues. Firstly, the only vinegar I had was so woosy that one could scarcely tell it was vinegar at all. It was a Coriole sweet aged red wine vinegar, to be precise. Secondly, I had no stock, either chicken or vegetable, so water had to do.
I thought I had free rein at this point to vary it as I pleased, and instead of cumin and paprika, I added ras el hahout.
Worked a treat!