Cook snap peas in boiling salted water until crisp-tender, 2 minutes. Transfer to bowl.
Return water to boil. Add noodles. Cook until tender but firm, 3 minutes (or as directed on package). Drain; rinse under cold water until cool. Transfer to large bowl. Toss noodles with sesame oil. Cut noodles with kitchen shears to shorten. Add peas, chicken, and green onions; toss with enough dressing to coat. Arrange salad on platter; top with toasted sesame seeds, if desired.
Per serving: 635 calories, 28 g fat, 6 g fiber Nutritional analysis provided by Bon Appétit