In a frying pan sprayed with nonstick cooking spray, brown meat. Add water, mushrooms (including liquid), and soup mix. Cover and simmer for 15 minutes. In a small bowl, blend yogurt and flour; add to meat mixture. Cook and stir on low heat until mixture thickens. Serve over hot noodles.
NOTES: For greater flavor with little or no fat add, substitute no fat beef broth or some wine for part of the water called for in the ingredients.