Heat a large frying pan. Add the olive oil and the steaks to you perfection. (I like mine rare, very rare.) Remove to a warm plate and add the wine and the garlic and onion. Sauté just a minute and deglaze the pan by scrapping the bottom with a wooden spoon. Allow the wine to reduce be half and then add the glace de viande and the rosemary. Simmer for a moment and add the butter mixed with the cheese. Mix with a wire whip until smooth.
Place a bit of the sauce on each plate and then a piece of the stake on top of the sauce. Add the salt and pepper at the very last, as salt will dry out the meat during the cooking process. Garnish with parsley.