Cook pasta according to package directions; drain. Place pasta in a large bowl.
Combine vinegar, 1 tablespoon of the sesame oil, vegetable oil, hoisin sauce, soy sauce, gingerroot, and garlic in a small bowl; stir well. Pour half of dressing over pasta, tossing to combine.
Heat remaining 1 tablespoon sesame oil in a large skillet over medium-high heat. Add pork; saute 3 to 5 minutes or until browned. Add pork to pasta mixture, tossing gently to combine.
Remove stems from spinach; wash leaves thoroughly. Cut spinach into thin strips. Cook in a large nonstick skillet over medium-high heat 3 to 4 minutes or just until spinach wilts. Add spinach to noodle mixture.
Sprinkle with sesame seeds, and pour remaining dressing over pasta; toss gently to combine. Add salt and pepper to taste. Serve warm.