The first thing you notice about Pho So 1, the first OC branch of a San Fernando Valley Viet chain, is that it has to be the most utilitarian dining space in the entire city of Irvine--a pho joint, which like the best of them, doesn't bother with much decor. The room is clean, sleek, so large it echoes, and so brightly lit it wakes you up even before you order the ca phe sua da. That is to say, it gets down to the basics, without much to see or distract. You eat. You pay. You get out. The pho is good for the city, but the mi is the thing to get. The broth is everything it always should be: the same recipe for the sweet, salty, clear yellow soup that every pho joint and Vietnamese restaurant that serves the dish uses. It's lubricant for the hair-thin egg noodles and the toppings, which are very good here. The roast pork is plentiful and thick, so tender and so soft it can be masticated by the toothless. The shrimp isn't overcooked and the noodles are still firm enough to be called al dente.