I have been a regular at NK for a very long time. I have had gallons of soup here and I would argue they have some of the best (thick) sate soup in the city. The broth is thick peanuty, with your choice of chicken, beef or and seafood, with just the right amount of spice.
The rest of the menu is standard Vietnamese fair, spring rolls are good, I take the salad rolls with no pork. Delicious.
But I come for the soup. It's awesome. It sorts me out. But beware, it has a nasty habit of leaving splash marks on dress shirts... Maybe it's just cause I eat like a wild animal...
I have brought a lot of NK "virgins" here and the feedback is the same. Great food. Good price. Fast efficient service.
It's too bad a couple people had bad experiences here and are dragging the rating down, it's a great spot, give it a shot, you will not be disappointed.
But either arrive before noon or wait until after the lunch rush as this place is JAMMED everyday... Usually the sign of a solid restaurant - just sayin'.