Moles for chow mien?

I wrote about a chow mien a while back as my b/f is a chow mien nut more to do with how its cooked rather than eating it. He believed it was to do with a master stock they used but when he created one it was far to salty. He now thinks its a oriental brown sauce that contains moles however what moles type would be suitable for this? Also there is a video in youtube a href="http://www.youtube.com/watch?v=RTEQ_nGn6uk" rel="nofollow"http://www.youtube.com/watch?v=RTEQ_nGn6…/a were the cook (ignore the idiots) adds a black thick type sauce can anyone guess to what it may be. It looks like oyster sauce however that sauce doesn't make the chow mien go dark? Thank you ppl