Break pasta into thirds. Cook in boiling water according to package directions; drain. Meanwhile, heat 1 tablespoon oil in large skillet. Stir-fry pork, garlic and pepper flakes until pork is browned. Remove from skillet and reserve. Heat remaining 1 tablespoon oil in skillet. Stir-fry cabbage, celery and green onions until tender-crisp. Add pasta, stir-fried pork and soy sauce to skillet; heat through.