Dissolve the salt in the water to make a brine.
Hydrate the flour by adding the brine in 3-4 additions, and briskly mixing between each addition with your hands.
Knead the dough into a ball and then transfer it to a clean work-surface to continue kneading.
Knead the dough 150-200 times or until the dough becomes extremely elastic and resilient.
Stretch the dough into a smooth ball and place it in a covered bowl to rest for 1.5 to 2 hours.
After the dough has rested, dust it with starch and press it into a thick disk using your hands.
Press the dough out in steps by lifting and pressing a rolling pin from the center of the disk away from you and then repeat pressing it in steps towards you.
Turn the dough 90 degrees and repeat step 7.
Now use the rolling pin to roll the dough out from the center and roll the dough in from the center.
Turn the dough 90 degrees and repeat step 9.
Dust the Udon dough with starch and starting from the corner closest to you, wrap the dough around the rolling pin. Roll them together until the sheet of dough is about ⅛-inch thick.
Unroll the dough and turn it 45 degrees. Dust the dough with starch and wrap it around the pin again, starting from the straight edge. Roll it around a few times to even out the thickness of the dough.
Unroll the dough and spread a generous amount of starch onto its surface. Fold the dough like a fan, staggering the folds so that they don't overlap each other.
Use a sharp knife to cut the dough into noodles using a single stroke.
Separate the strands of Udon and dust with more starch to keep them from sticking together.
To boil the Udon, heat a large pot of water to a boil.
Dust off any excess starch and add the noodles to the boiling water. Stir-for the first 30-seconds to keep them from sticking together.
Boil the noodles until they're translucent (12-13 minutes for ⅛-inch thick noodles) and then drain and rinse the Udon with cold water to remove any excess starch. For serving suggestions, check the headnotes above.