1.Season The Steak With Salt And Pepper To Taste. Heat The Olive Oil In A Skillet Over Medium-High Heat. Cook The Steak Until Nicely Browned On The Outside, And Nearly Cooked To Your Desired Degree Of Doneness On The Inside, 3 To 4 Minutes Per Side For Medium-Rare. An Instant-Read Thermometer Inserted Into The Center Should Read 130 Degrees F (54 Degrees C). Remove The Steak From The Pan, And Tent Loosely With Foil To Keep Warm. 2.Wipe The Oil From The Skillet, And Pour In The Red Wine; Simmer Until Reduced By Half. Whisk The Flour Into The Beef Broth, Then Stir Into The Simmering Red Wine Along With The Rosemary And Dijon Mustard. Return To A Boil; Cook, Stirring Constantly Until The Sauce Reduces Slightly And Thickens. Keep Warm Over Low Heat. 3.Cut The Meat From The Bone, Then Slice Into 1/3-Inch Thick Pieces. Serve With The Rosemary Sauce.