Dashi, a stock made from dried fish and seaweed, is the classic base for udon soup.
- 8 medium Japanese-style dried anchovies,(iriko)
- 2 (2" × 15") pieces of kombu (dried seaweed used for soups)
- 1⁄2 cup katsuobushi (dried bonito flakes), lightly packed
- Sea salt
- Cold Udon
- Toasted sesame seeds
- Scallions, finely sliced
Cut off and discard the heads from the anchovies. Drop fish into a small pot.
Next, wipe off the kombu with a damp towel and cut each piece into quarters. Put the kombu into the same pot as the iriko and pour in 6 cups cold water. Place pot over high heat. Just before the water comes to a boil, fish out the iriko and kombu using tongs.
Sprinkle katsuobushi into pot. Cover pot, remove from heat, and let bonito steep for 4 minutes. Strain liquid and season with sea salt to taste. You will have about 5 cups. To serve, pour hot dashi over bowls of cooked noodles and sprinkle with toasted sesame seeds and finely sliced scallions.