Cook linguine as directed on package; drain. Meanwhile trim fat from beef steak. Cut beef with grain into 2-inch strips; cut strips across grain into 1/8-inch slices. (For ease in cutting, partially freeze beef about 1 1/2 hours.) Toss beef and 1 teaspoon cornstarch. Mix water, soy sauce, 1 tablespoon cornstarch, the brown sugar, vinegar, sesame oil and pepper.
Heat wok or 12-inch skillet until very hot, Add 1 tablespoon vegetable oil to wok; rotate wok to coat side. Add beef and gingerroot; stir-fry about 3 minutes or until beef is brown. Remove beef mixture from wok.
Add 1 tablespoon vegetable oil to wok; rotate wok to coat side. Addd broccoli, mushrooms, bell pepper, and onions; stir-fry about 4 minutes or until vegetables are crisp-tender. Stir in soy sauce mixture. Cook and stir about 1 minute or until thickened. Stir in beef mixture and linguine. Heat through. 4 servings.