I struggled with whether to just add to the last thread on this subject, but tasting my first Bahn Mi yesterday was such a momentous discovery I had to put it where more Chowhounders would see it, at the very front of the line.
I finally made it to Bahn Mi So 1 on Broome right off Mott, and ordered a #1 (Dac Biet, $2.75). The very sweet woman behind the counter asked if I wanted hot sauce, and I said yes. What was handed to me was an almost foot-long baguette filled with sweet bbq pork, the "pork roll" mentioned by other posters, julienned pickled carrot, cucumbers, fresh cilantro, and a creamy, spicy sauce that left a little heat but was in no way overpowering. I can't believe I've never eaten this before! There were so many complimentary flavors exploding on my palate: it was SO good I am already plotting when I can get there again. And for $2.75, it's the best sandwich deal in the city. So thank you, Bahn Mi enthusiasts: it's the best food discovery I've made in months.