Kalguksu (Knife-cut Noodle Soup)

Variations

• The noodles go straight into the broth — and unlike most dishes that do that, this one does not want their starch. Pasta e fagioli also cooks its pasta in the liquid it serves, and there every bit of starch the pasta sheds stays in the pot and thickens it, on purpose. Kalguksu is built on a clear anchovy or clam broth, so the same starch is an obstruction. Same move, opposite aim.
• Which is where the rule about brushing the flour off comes from. The dusting flour on hand-cut noodles is there to stop them sticking to each other; in the pot it simply dissolves and clouds the broth. For a clear bowl, brush it off or boil the noodles separately; for a thick one, put them straight in. Both are traditional.
• Being knife-cut is not only a name, either. Orecchiette sets out the ways of shaping a noodle on this site, and kalguksu is the rolled-and-cut one while Lanzhou lamian is pulled. A cut noodle has a square section, so it has edges for broth to catch on; a pulled noodle is round and the broth runs off it.
• Bajirak kalguksu: with purged clams, for a briny, clean broth.
• Chicken kalguksu: rich broth and meat from a simmered chicken.
• Perilla kalguksu: ground perilla seed stirred in for a nutty bowl.
• Pat-kalguksu: a southern version cooked in sweet red-bean broth.

Tips

• Pull the kelp out before it boils to avoid bitterness and sliminess.
• Brush the flour off fresh noodles so the broth does not turn cloudy.
• Do not overcook the noodles — take them out slightly underdone.
• Season with soup soy sauce plus salt for clean colour and taste.
• Add the seasoning sauce if you like it spicy.
• Underdone is right because the noodles keep cooking in the bowl. The broth's heat finishes them, and while it does they go on drinking it and swelling. Mie goreng builds its whole method on that same property.
• Seasoning with soup soy sauce alone darkens the broth. The division here is that the soy brings colour and a fermented savour and salt supplies the rest of the saltiness (salt and seasoning).
• The kelp comes out before boiling because the bitter compounds leave at higher temperatures than the savoury ones do. Take the glutamate that comes out at 70-80°C and stop there (building umami).