Thai Peanut-Sesame Noodles

3 tablespoons soy sauce
2 tablespoons rice vinegar or white-wine vinegar
1/2 teaspoon dried hot red pepper flakes, or to taste
2 tablespoons firmly packed brown sugar or granulated 
1/2 cup creamy peanut butter
1 tablespoon Oriental sesame oil
1 teaspoon grated peeled fresh ginger root
1/2 cup chicken broth
1 pound linguine or lo mein noodles
chopped scallions and cucumber strips for garnish

In a saucepan combine the soy sauce, the vinegar, the red pepper
flakes, the brown sugar, the peanut butter, the oil, the ginger
root, and the broth, simmer the mixture, stirring, until it is
thickened and smooth, and let it cool slightly.

In a kettle of boiling salted water cook the noodles until they
are al dent, drain them in a colander, and rinse them under cold
water.  Drain the noodles well, transfer them to a bowl, and toss
them with the sauce.  Serve the noodles at room temperature and
garnish them with the scallion and the cucumber.