I'm so fed up of recipes (usually in a magazine or paper) that have one non-obtainable ingredient. I live in a large city - not London, so maybe that's the problem - and wanted to make a cake, having seen the recipe in the paper.
It required pomegranate syrup. The assistants at the big Sainsburys I went to had never heard of it, but checked, and they didn't stock it. If it's not PS, it's another unusual ingredient.
The trouble is that I have no idea of what it's like, so don't know what to substitute it with.
Yes, I know, a real 1st world problem. but still annoying, as it happens a lot. Mind you, a lot less since I stopped using Ottalenghi recipes.