1) In shallow dish or plastic food storage bag, combine flour, salt and pepper; mix well. Add beef; toss to coat. Remove beef from bag; place on plate. 2) In small bowl, combine broth and remaining flour mixture from bag; blend well. Set aside. 3) Spray medium nonstick skillet with nonstick cooking spray. Add oil; heat over high heat until hot. Add beef; cook and stir 2 minutes. Reduce heat to medium-high. Add onion; cook and stir 2 minutes. Add mushrooms; cook 4 minutes stirring occasionally. Stir in broth mixture; bring to a boil. Reduce heat; simmer 5 minutes to blend flavors. Remove skillet from heat; stir in sour cream. 5) Pour mixture into freezer container; cover tightly. Refrigerate until completely cooled. Store in freezer until ready to use. 6) To serve, cook noodles to desired doneness as directed on package. Drain; cover to keep warm. 7) Meanwhile, thaw and heat beef mixture, place mixture in microwave save dish; cover with vented microwave-safe plastic wrap. Microwave on HIGH for 5 minutes. Break mixture into pieces with spoon. Microwave on MEDIUM for an additional 6 to 9 minutes or until thoroughly heated, stirring once halfway through heating. Serve beef mixture over noodles.