Cook and drain noodles as directed on package, omitting salt. Place on serving platter or in serving bowl; cover to keep warm.
Meanwhile, sprinkle beef with peppered seasoned salt. Heat 10-inch nonstick skillet over medium-high heat. Add beef; cook and stir 2 minutes or until brown.
Stir in tomato sauce, mushrooms and onions (if necessary, break up larger pieces of tomatoes with spoon). Heat to boiling. Reduce heat to low; simmer uncovered 3 to 5 minutes, stirring occasionally, until vegetables are tender. Pour beef mixture over noodles; toss gently to mix.