Isak Hongdukkae Kalguksu is a Korean restaurant in Junggok-dong, Seoul, serving kalguksu (knife-cut noodles), anchovy noodles, and kongguksu. Kalguksu comes with geotjeori, and the restaurant also makes crispy gamjajeon. The kalguksu and gamjajeon are inexpensive and flavorful. The geotjeori has a particularly good flavor.