Mix flour and water together to form a firm dough. Knead the dough for 3 to 5 minutes. Cover the dough with cold water and let sit for 5 to 10 minutes. Next, knead the dough in the water, gently, until the water turns milky. Pour the water off. Now cover the dough with warm water, and knead again until the water turns milky again. Repeat adding cold water, kneading, adding warm water and kneading until the water finally becomes more clear. This process washes out the white starch and the brown bran from the dough leaving you with a spongy mass called wheat gluten which is the wheat protein.
Bring 3 cups of water to a boil. Place the gluten in the boiling water and boil uncovered for 5 minutes. Reduce the flame to medium and add the shoyu. Cover and bring to a boil. Reduce the flame to medium-low and simmer for 25 to 30 minutes. The gluten becomes brown, soft, tender and salty. This is now called seitan.
Per serving - 209 calories, 1 g fat (5% calories from fat), 9 g protein, 44 g carbohydrate, 7 g fiber, 0 mg cholesterol, 341 mg sodium