Over medium-high heat, heat 2 tablespoons oil and brown the beef stew meat. Add beef broth, wine, black pepper, salt, spicy brown mustard, and worcestershire. Bring to a boil and simmer until beef is tender. Sautee mushrooms and onions in remaing tablespoon of oil until onions are translucent and add to broth. Bring to a boil and add a mixture of the water and flour to make the gravy. Add the yogurt. Simmer for approximately 10 minutes to cook out the starch from the flour. Meanwhile cook egg noodles according to directions, and serve the stroganoff over the noodles.