Combine tenderloin, onion, salt, pepper, and garlic. Set aside. Cook pasta. While pasta is cooking, heat olive oil in 10 inch skillet and saute mushrooms. Remove mushrooms from skillet, add 1 T olive oil to skillet and add meat mixture. Saute meat mixture until meat is browned. When meat is fully browned, add cooked mushrooms, beef broth and worcestershire. Cover and heat thoroughly. Add yogurt slowly and stir to melt. Add pasta directly to pan and stir to combine.