Sanuki Udon: Kagawa's Signature Noodle and the Philosophy of Koshi

Ingredients

• 500 g ASW (Australian Standard White) wheat flour, 10–11% protein content; or highest-protein bread flour available as substitute
• 5 g fine salt, dissolved in the water before mixing
• 240 ml cold water, divided — primary hydration plus small additional measure
• For kake broth (konbu-iriko dashi)
• 1 litre water
• 15 g dried konbu, wiped clean with a damp cloth
• 30 g iriko (niboshi / dried sardines), heads and entrails removed to reduce bitterness
• 30 ml soy sauce
• 20 ml mirin, Kagawa style tends to a slightly sweeter balance than Tokyo tsuyu
• For cold zaru tsuyu
• 200 ml strong konbu-iriko dashi, as above
• 40 ml soy sauce
• 30 ml mirin, slightly more than Tokyo proportion; Kagawa preference

Method

1. 1
   Dissolve the salt thoroughly in the cold water. Add the salted water to the flour in two stages — the primary measure first, working the liquid into the flour with the fingertips until shaggy, then the remainder — until a rough, stiff dough forms. The dough will appear dry and uneven at this stage. This is correct: resist the impulse to add more water. The dough is done when no dry flour remains loose in the bowl.
2. 2
   This is where the dish lives or dies. Seal the dough inside a heavy ziplock bag and place it on a clean floor surface. Using both feet in an even, controlled stomping pattern, apply body weight across the entire surface of the dough — 50 to 60 passes each side. Fold the dough, return it to the bag, and repeat until it is smooth and cohesive with no cracks at the edges. This fumikomi (foot kneading) achieves the even gluten development that hand kneading alone cannot produce. The finished dough feels dense, smooth, and uniformly firm under the hand.
3. 3
   Wrap the kneaded dough tightly in plastic film and leave it to rest at room temperature for a minimum of 1 hour and up to 2 hours. This is the ne-kashi — gluten relaxation. The dough will soften perceptibly and become noticeably more pliable than when it was wrapped. Do not skip or shorten this stage; dough rolled before full relaxation is resistant and rolls unevenly, producing noodles without proper koshi.
4. 4
   Lightly flour a clean work surface. Using a long rolling pin, roll the rested dough out to an even sheet of approximately 3–4 mm thickness, rotating and flipping the sheet regularly to maintain even pressure across its whole surface. Fold the sheet loosely into thirds and, with a sharp knife, cut noodles approximately 3–4 mm wide — the width should equal the thickness for an even, square cross-section. The cut noodles should hold their shape without sticking; dust lightly with flour to separate if needed.
5. 5
   Bring a large pot of unsalted water to a full, rapid boil. Add the noodles and stir immediately to prevent sticking. Boil at a vigorous roll for 10 to 15 minutes. Begin testing at 10 minutes by pressing a single noodle gently with chopsticks: the noodle is done when it springs back visibly — this springback is the physical verification of koshi. The surface should appear smooth and slightly translucent. Remove one noodle and bite through it: the centre should offer no raw, chalky resistance.
6. 6
   For kake (hot) service: drain the noodles and divide into warmed bowls; ladle over the hot konbu-iriko dashi seasoned with soy and mirin. The broth should smell clean, faintly marine, and sweet — the dried sardine sweetness of Kagawa. For zaru (cold) service: drain the noodles immediately into ice water, rinse firmly with the hands to remove surface starch, and drain again. The cold rinse firms the noodle's koshi and the surface should feel silky and taut. Serve on a bamboo zaru with the tsuyu alongside for dipping.