Add flour, salt, and water to a large mixing bowl, stir with a pair of chopsticks or a spatula until all the ingredients are roughly mixed.
Knead the dough with your hands for about 5 minutes until it forms a roughly smooth dough. (It's okay if the dough is not perfectly smooth right now. It will become smoother after resting.)
Cover the dough with plastic wrap, let it rest under room temperature for 45 minutes.
After 45 minutes, take off the plastic wrap and flip the dough so that the smoother side is facing down. Knead the dough with your hands for 3 minutes until it becomes smooth.
Take the dough and divide it into 8 equal pieces. Roll each piece into a sausage shape that is approximately 3½ inches in length and 1 inch in diameter.
Pour ¼ cup of vegetable oil onto a plate and coat each piece of dough with oil by rolling them in the oil one at a time, until all pieces are coated evenly. Once coated, place all the dough pieces on the plate with the oil and cover them with a piece of plastic food wrap. Allow them to rest at room temperature for 1 hour.
Once the dough has rested for 1 hour, take one piece and place it on your working surface. Use your palm to flatten the dough into a thin sheet that is approximately 2 inches wide and 6 inches long.
Press down on the center of the dough sheet using the back of a knife. Make sure you don't cut it through. This will create a trace that looks like the vein running down the middle of a leaf. Set it aside. Repeat until you flatten all the dough pieces into leaf-like sheets.
Hold two ends of a dough sheet, stretch and slap it onto the working surface to make a "biang biang" sound. Continue stretching the dough until it reaches a length of approximately 3 feet.
Find the center of the noodle and tear it apart along the middle trace until it forms a loop, set it aside. Repeat until you stretch all the dough sheets into noodles.
Fill a large pot with water and bring it to a boil. Add the noodles and cook them for 3 to 5 minutes or until they are floating on the surface. If your pot isn't big enough, you may need to cook the 8 noodles (for 2 servings) in two separate batches to prevent them from sticking together.
Strain the noodles, place them into a serving bowl. Top with the sauce, combine well, and serve hot.