This afternoon I had lunch at a small Szechuan restaurant in Palo Alto, and ordered their dan-dan noodles, expecting to get the fiery noodles with chili oil, preserved vegetable, and pork that I have a) had at other Szechuan restaurants around here and b) have made myself from a Szechuan cookbook. Instead, I got noodles with peanut sauce. Tasty, but not at all what I expected. I asked my waitress (also an owner, I believe), and she said there were two kinds of dan dan noodles, but that this is the one that they regularly serve unless people specify the other (she said what the other was, and it sounded like dan-dan mien, but it was in Chinese and I couldn't really catch it that well).
So, my question is whether this should have surprised me--both that this peanut-sauce variety exists (and would be served to me), and that there are in fact two kinds of (completely unrelated) dan-dan noodles? I would have thought that if a restaurant listed dan-dan noodles and that's what I ordered, I would have gotten the other. But maybe since I'm not Asian, they assumed I didn't want the authentic kind? I'm confused and would appreciate insight!