In a large nonstick skillet coated with cooking spray, cook beef in 1 tablespoon oil until no longer pink; drain and set aside. , In the same skillet, saute onion and green pepper in remaining oil for 1 minute. Stir in mushrooms; cook for 3-4 minutes or until tender. Stir in 1 cup broth, tomato sauce, sherry or additional broth, Worcestershire sauce, mustard, paprika, bay leaf, thyme and pepper. Return beef to the pan; bring to a boil. Reduce heat; cover and simmer for 40-50 minutes or until meat is tender. , Cook noodles according to package directions. Meanwhile, combine flour and remaining broth until smooth; gradually stir into beef mixture. Bring to a boil; cook and stir for 2 minutes or until thickened. Discard bay leaf. Remove from the heat; stir in sour cream until blended. Drain noodles; serve with stroganoff.