Fully dissolve salt in water.
Sift flour, mix in salt water little by little.
Form a ball — won’t look smooth, but no dry clumps. Cover, rest 30 min.
Knead: fold dough into itself + foot-press, x3–4. Rest 10 min.
Repeat knead + rest.
Wrap tightly, rest. (Chewier: overnight fridge rest, room temp before rolling.)
Roll on a well-floured surface to desired thickness (common mistake = too thick, aim thinner).
Fold accordion-style, dusting flour well between layers (noodles stick as you cut), then cut.
Boil in UNSALTED water at a hard rolling boil the whole time, ~20 min (depends on thickness).
Rinse cold, rubbing off surface starch, then ice-shock.
Cook mirin + sake until alcohol cooks off.
Add water, soy sauce, dashi powder.
Light boil, off heat, cool immediately.
Fridge until cold.
Lightly sear beef.
Add soy sauce, sake, mirin, sugar, water.
Simmer a few min, skimming scum. Keep saucy — don’t reduce down (reduced soy = salty). Cool.
