I was given a bottle of "special sauce" which was a bit like thai chilli sauce only it was thicker, and not "clear" in that it was more like a liquidy fine textured chutney (kind of glooped out of the bottle). I could detect chilli, vinegar, mustard seeds, some dried vine fruit, possibly dates, brown sugar onions/shallots and powdered spices.
It was not as garlicky as sweet chilli sauce and was finely minced and syrupy so it was like a homepsun HP sauce but much more sweet and with more chilli and deeply flavoursome.
The maker wouldn't share the recipe!
Anyone got any similar recipes knocking about?