Khao Soi in Herndon

Khao soi is the noodle dish Northern Thailand is best known for: a coconut curry broth, soft egg noodles beneath it, and a tangle of the same noodles fried crisp on top. We serve it every day, at lunch and at dinner, for $18.95.

Northern-style curry, egg noodles, crispy-skin chicken, pork chashu, a seasoned egg and pickled radish, finished with the crisp fried noodles on top. The pork chashu and the seasoned egg are our own additions.

Khao soi belongs to Lanna, the old northern kingdom centred on Chiang Mai, and it carries the traces of the trade routes that ran through it — the curry owes a good deal to the Burmese and Yunnanese Muslim traders who moved along them. It is a separate tradition from the central Thai cooking most people meet first, and it tastes like it: rounder, less sharp, built on coconut rather than on chilli and lime.

Push the crisp noodles down into the curry as you go. They soften into the broth but keep some bite, which is the whole point of them. The pickled radish is there to cut the richness — take a little with each few mouthfuls rather than all at once.

If khao soi is what brings you in, the rest of that side of the menu is worth knowing: Kaeng Hung Lay, the northern ginger curry; Boat Noodle Soup; and Yen Ta Fo. Isan dishes from the northeast sit alongside them, and the Thai classics are all still there.

We are at 171 Elden Street, Unit 130, Herndon, VA 20170 — the office building next to Virginia Tire & Auto, with free parking outside. We are a short drive from Reston, Sterling and the rest of Fairfax County, and minutes from Dulles Airport. Lunch is 11:00 am to 3:00 pm every day. Dinner is 5:00 to 10:00 pm Sunday through Thursday, and 5:00 to 11:00 pm on Friday and Saturday. Call 703-467-0111.