Break noodles into small pieces and fry as directed on package, until they puff up. Drain and set aside. Cook chicken in microwave until almost done, then slice into strips and toss to coat in Teriyaki sauce. Return to microwave and complete cooking. Shred lettuce (narrow strips) and chop green onion. Place lettuce, chicken, onion, and noodles in a large bowl. Add a small amount of vinegar for "dressing" and toss well.

(Alternatively, I semi-freeze the chicken first, making it easy to slice into strips. Then, marinate the strips in the teriyaki sauce before cooking.)