Back before China started dealing with the US, all of the Chinese ingredients I could get for Chinese cooking was from Taiwan, and there was much less available, than there is now. However, one ingredient I used to get I could never find a replacement, that was the same - a Szechwan "Chili Paste With Garlic", which is a fermented chili paste, that had the best flavor of any I ever had. Other brands I tried, once they stopped selling that, and only had the Chinese brands, just didn't taste the same, though many years later, I found one almost as good, made in Thailand, even though it's a Chinese ingredient! I think both of them were fermented much longer than all the other brands, giving the better flavor. I even tried making it myself, but it was nothing like it.