In a large skillet heat olive oil and butter until hot. Season fillets with salt and pepper and sear in pan until brown on both sides and cooked to medium rare. Remove to plate and tent to keep warm.
Add mushrooms to same pan and cook until softened. Season with salt, pepper and hot sauce. Then add shallot and cook until soft. Add garlic and cook for 30 seconds. Off heat add brandy and ignite. Once flames die down cook until almost gone. Then add beef broth, lemon, cream, Worcestershire sauce, and mustard. Cook until slightly thickened and reduced. Off heat stir in herbs and butter until melted. Pour over steaks and serve.