Heat a heavy skillet which has been sprayed with a noncaloric vegetable spray.
Place the tenderloin strips in hot pan and brown, turning once.
Remove the meat and keep it hot.
Deglaze the pan with the burgundy, stirring to loosen any particles of beef clinging to the pan.
Add the beef broth, mushrooms, green onions, and seasonings.
Reduce the mixture until it becomes slightly thick.
Add the yogurt, stirring only enough to combine.
Do not let the mixture boil, as the yogurt will separate.
Garnish each tenderloin with some of the sauce.