Wuhan 热干面. I have no way of determining the authenticity, but the noodles were not bad, springy, with a good sesame sauce flavour.
I haven't had reganmian very often, but it seems that Cai Lin Ji is the quintessential vendor for it in China, and fortunately they just opened an outlet down at Jurong Point (1 Jurong West Central 2 #03-56).