These chewy Japanese wheat-based noodles are often served with hot broth as a soup or stir-fried. Or, simply cook and serve with soy sauce and mirin, and garnish with chopped scallions and shaved nori.
To prepare the dough, in a bowl, dissolve the sea salt in warm water. In a separate mixing bowl, sift the flour and starch.
Next, make a well in the flour bowl and pour about 1/2 of the water into the well. Mix with both hands and all fingers, scraping the bottom of the bowl as you mix until the water is incorporated.
At this point, add about 1/2 of the remaining water and continue to mix until the dough begins to separate into strands. Finally, add the rest of the water and mix and squeeze the dough together until it binds into a ball. The dough will not be smooth at this point but will begin to show elasticity. Let the dough rest in the bowl for 30 minutes.
To knead the dough, on the countertop, sprinkle on a bit of corn or tapioca starch, just enough to prevent the dough from sticking. Remove the dough from the bowl and place on the lightly–dusted counter. Knead until very smooth and shiny, about 8 to 10 minutes. At this point, form the dough into a tight ball and rub with a bit of oil. Place the dough ball into a clean bowl, cover with a cloth and allow to rest for 3 to 4 hours before rolling.
To roll out the dough, sprinkle some corn or tapioca starch on the counter and roll out until the dough is 1/8 to 1/4 inch thick. Note that the noodles will expand when they cook.
Before cutting the noodles, sprinkle the dough lightly again with corn or tapioca starch and spread over the entire dough surface. Grasp the far edge of the dough and fold it in half toward you to meet the close edge. Sprinkle and spread some more corn starch and bring the far edge toward you again, folding in half a second time. Spread some more corn or tapioca starch on the top and let the dough rest for another 30 minutes.
Once the dough has rested, apply a slightly heavier amount of corn or tapioca starch on top and some additional starch on the counter. This will help make sure the noodles do not stick together when cutting.
With a sharp chef’s or similar knife, begin cutting the dough crosswise into noodles 1/8 to 1/4 inch wide. After cutting the noodles, separate to prevent them from sticking together, using more starch as needed.
Set the noodles aside on a dusted counter or tray until ready to cook
Cook the noodles in boiling salted water, stirring occasionally until they float to the surface, about 3 minutes, continue to cook for an additional 2 minutes once floating at the top, but careful not to overcook since they will get slightly rubbery. Test for fineness before removing from water. Lift them out with a spider and place them immediately into ice cold water until it is time to serve.
Note: These noodles are excellent as leftovers and frozen. To freezer, form small piles on a plate or sheet pan (portion size), and place in freezer. Once piles are frozen, place then in ziplock bags and add frozen noodles directly to hot water or soup to cook for a quick meal.