Boil the noodles in a large pot of well-salted water until tender. Drain, cool thoroughly in cold water, and drain again. Toss the noodles with the sesame oil. Cover and refrigerate for 1 hour. Mince the fresh chile pepper, the scallions and the cilantro. Peel and seed the cucumber and cut into fine julienne. In a large bowl, combine the sesame seed paste, peanut butter, vinegar, Hunan pepper sauce, chile, sugar, chicken broth and white pepper. Add the cold noodles and toss well. Add the cucumbers, scallions and cilantro, toss again, and serve.